CHEMISTRY FORM ONE TOPICAL EXAMINATIONS
TOPIC : 1  INTRODUCTION TO CHEMISTRY

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

INTRODUCTION TO CHEMISTRY.



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils

SECTION A 20 MARKS

  1. MULTIPLE CHOICE QUESTIONS

  1. The term chemistry means;

  1. Study of nonliving things

  2. Study of physical properties of matter

  3. Study of drugs

  4. Study of composition and decomposition of matter

  1. Substances studied in chemistry are made up of;

  1. Compounds

  2. Matter

  3. Chemicals

  4. Element

  1. Which is not an importance of studying chemistry;

  1. Understand how matter undergo chemical change

  2. Make various medical products

  3. Understand the use of chemicals in agriculture

  4. Help us enter into various careers.

  1. A mother at home can apply chemistry to;

  1. Weed flowers in the garden

  2. Dusting the floor of her house

  3. Weighing maize flour

  4. Cooking food in the kitchen

  1. Which of the following illustrates a chemical reaction taking place in our body

  1. Falling sick

  2. Digestion

  3. Respiration

  4. Salivating

  1. Which of the following is not a list of application of chemistry?

  1. Table, chairs and Bricks

  2. Shoe polish, antiseptics and toothpaste

  3. Soap, medicinal drugs and perfumes

  4. Fertilizer, pesticides and herbicides

  1. Which of the following careers does not require the knowledge of chemistry?

  1. Medicine

  2. Agriculture

  3. Archeology

  4. Pharmacy

  1. Identify the skill not acquired during chemistry study

  1. Careful observation

  2. Accurate reporting

  3. Testing hypothesis experimentally

  4. Map reading skills

  1. Individuals who studied chemistry long time ago were called

  1. Alchemists

  2. AL chemistry

  3. Witch doctors

  4. Chemists

  1. Chemistry is list related to;

  1. Biology

  2. History

  3. Physics

  4. Geography

  1. MATCHING ITEMS QUESTIONS.

LIST A

LIST B

  1. Study of matter

  2. Wanted to convert metals into precious metals

  3. Sense not commoly used in laboratory

  4. Deals with making and dispensing of drugs

  5. Deals with study of living and non -living things

  6. Breaking up of matter

  7. A person who studies chemistry

  8. Anything that has got mass and occupies space

  9. A chemical applied in plants to supply nutrients

  10. Deals with development of new products.

  1. Engineering

  2. Technology

  3. Alchemist

  4. Fertilizer

  5. Eyes

  6. Tongue

  7. Composition

  8. Decomposition

  9. Chemist

  10. Pharmacy

  11. Nursing

  12. Medicine

  13. Matter

  14. Atom

  15. Chemical engineer

  16. Science

  17. physics



  1. Write T for true statement and F for a False statement.

  1. There are only two branches of science

  2. Chemistry has little application in our life

  3. Through chemistry, development of modern technology is made possible

  4. We only study chemistry to enter into careers

  5. Chemistry is only studied by chemists

b) Fill in the spaces below;

i) The field of science that deals with crop production and livestock management is called……………

ii) Ink, shoe polish, paper, clothes and rubber are examples of things produced from application of knowledge of…………………………………………………….

iii) Study of chemistry prepares people for different skills needed in our daily life such as………….

iv) Chemicals used to kill insects are called………………………………………………………..

v) The study of matter and its properties is called…………………………………

  1. A) mention three branches of science

b) Who is a chemist?

c) List 5 places where chemistry is applied

d) Name three cleaning agents made by chemistry knowledge



  1. Explain how chemistry is applied in the following;

  1. Health

  2. Agriculture

  3. Energy production

  4. Transport

  5. Modern technology

  1. Mention four importance of studying chemistry

  2. Mention two items used in each of the following categories that are made through application of chemistry

  1. Agriculture

  2. Pharmaceutical

  3. Household items

  4. Food and beverages

  5. Transport

b) Chemistry has contributed to environmental hazards. Briefly explain how



  1. a) Who are alchemists?

b) What was the aim of alchemists?

c) Briefly explain how chemistry has contributed to good life



  1. a) Mention areas where chemistry is applied.

b) Mention five careers one can enter by studying chemistry.



  1. a) mention two branches of chemistry

b) Differentiate chemistry from physics.





LEARNINGHUBTZ.COM Page 4


TOPIC : 2  THE LABORATORY

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

CHEMISTRY LABORATORY



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils



SECTION A:

        1. Choose the best answer from the given statements, and write it in the table provided below;

  1. Which of the following warning signs is likely to appear on a bottle containing concentrated nitric acid in the laboratory?

  1. Corrosive

  2. Explosive

  3. Irritant

  4. Flammable

  1. When a chemist studies a substance h/she is interested in its;

  1. Force of attraction

  2. Properties

  3. Shape

  4. Smell



  1. Certain activities are required in order to manage laboratory techniques and safety. There are;

  1. Laboratory rules to be observed

  2. First Aid to be used

  3. Warning signs and protective symbols to be used

  4. All of the above



  1. What can be the cause of fires in the laboratory;

  1. Exposure of flammables to heat and open fires

  2. Improper treatment of explosive and highly reacting substances

  3. Performing experiments without permission and without protection

  4. All of the above



  1. What might happen to a careless pupil in the laboratory?

  1. He may get injuries

  2. He will not achieve in studies

  3. He will cause loss of things

  4. Nothing will happen



  1. A person who loses too much blood due to an accident is likely to go into;

  1. Burns

  2. Shock

  3. Sores in his/her mouth

  4. Painful wounds



  1. Which one of the following statement does not show that chemistry knowledge has been applied?

  1. Rock and earthly materials are changed to iron and steel

  2. We obtain processed food stuffs and drinks from industries

  3. Pharmaceutical works provide with various types of medicine

  4. We can enjoy music produced by the best singer



  1. A booklet containing guidelines for first Aid is a;

  1. Chemistry book

  2. First kit

  3. First Aid manual

  4. First Aid component



  1. A form one student found a bottle with a sign of a skull and crossed bones. The sign means;

  1. Toxic

  2. Irritant

  3. Flammable

  4. Explosive



  1. Which of the following is not among the instruments and chemicals used for First Aid?

  1. Pair of scissors

  2. Mosquito net spray

  3. Assorted bandages

  4. Sterilized cotton wool

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2. Match the items of column B to those of column A for meaningful statements and enter the answers in the table provided below;



COLUMN A:

  1. Gas poisoning

  2. A laboratory rule

  3. Usually applied on fresh wounds and bruises

  4. Used to protect the clothes of a caregiver against dirt and fluids such as blood, pus from the patient or victim.

  5. Explosion

  6. A measure taken to protect people or things against possible harm or trouble

  7. Fertilizers, drugs, detergents

  8. Can poison you and can cause immediate death

  9. Apparatus

  10. Symbol for magnesium element



COLUMN B:

  1. Apron

  2. No fume chamber

  3. Oral ingestion

  4. Chemistry application

  5. Things which are used to carry out experiments in the laboratory

  6. Iodine tincture

  7. Pain killers

  8. Precautions

  9. Toxic

  10. Mg

  11. Corrosive

  12. Be calm and silent

  13. A forceful rapid reaction which involved throwing off particles at high speed and releasing energy such as heart and loud sounds.

  14. Mn

  15. History

  16. Harmful

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SECTION B:

Answer these questions only shortly and briefly.



  1. (a) Write TRUE for a correct statement and FALSE for a false statement, in the

Following;

  1. The hazard label for petrol is normally flammable sign which means catches fire easily ……………..

  2. Fuels and chemicals such as plastics, pesticides, perfumes, detergents are the products made from soil and natural gas. ……………….

  3. A form one student found a bottle with a sign of a skull and crossed bones. The sign means explosion. ………………

  4. Never keep toxic materials in children’s’ reach areas since they may poison them ……………..

  5. Experiments in which poisonous gases and vapour are produced, must not be carried out in a fume chamber. ……………………

  6. A school laboratory should always be clean and well arranged ………………



  1. What is the purpose of doing experiments in the learning of chemistry? ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

  2. (a) What is the aim of using warning sign on containers in the chemistry laboratory? ………………………………………………………………………………………………………………………………………………………………………………………………

(b) Name one example of a protective symbol ………………………………………………………………………………………………



  1. In the space below, draw clear and neat warning signs found on containers

  1. Corrosive (iii) Explosive



  1. High flammable/ inflammable

  1. Write name of one chemicals under each of the following

  1. Oxidant/oxidizing agent ……………………………………………………………

  2. Toxic/poison …………………………………………………………………………

  3. Harmful/ irritant ……………………………………………………………………...



  1. Draw the following warning signs

  1. oxidant (b) flammable



  1. State three areas where chemistry knowledge is applied in day to day life; and give TWO examples in each area.

Area

Example

i.


ii.


iii.








  1. Complete the following table;



FIRST AID KIT

  1. A pair of scissors

Diagrams

Quantity

Used for

How used


1


Measuring body temperature.


  1. Sterilized cotton wool












1 reel

Washing












  1. Name six injuries which can be caused by running in the laboratories or in the corridor of it.

  1. ……………………………………………………………….

  2. ………………………………………………………………..

  3. ………………………………………………………………..

  4. ………………………………………………………………..

  5. ……………………………………………………………….

  6. ………………………………………………………………..









SECTION C:

Include only the necessary points in answering the following questions.



  1. How can you help a fellow student who has been injured by a chemical splash into his/her eyes?



  1. As a safety measure it is stated that “wear protective equipments when doing dangerous experiments”. How you can explain this



LEARNINGHUBTZ.COM Page 5


TOPIC : 3  FIRST AID

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

FIRST AID



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils



SECTION A: 20 MARKS

1.Choose and write the letter of the best answer in each of the multiples choices in the space provided;



  1. Which one is the correct meaning of first aid kit;

  1. An immediate help given to an accident victim before attending the hospital.

  2. A small box consists of metal tools only.

  3. A bag consists of books and chemicals.

  4. A small box consists of different instruments and chemicals in assisting an accident victim.



  1. What is chemistry?

A. The branch of science which deals with the study of life

  1. The branch of science which deals with the study of energy, force, mechanics, waves and the structure of atoms and the physical universe.

  2. The branch of science which deals with the study of properties, composition and structure of matter and the changes matter undergo.

  3. The help that one is given before attending to the hospital.



  1. What do you call an instrument which is used in holding chemicals and heating chemicals;

  1. Measuring cylinder

  2. Gas jar

  3. Test tube

  4. Funnel



  1. When one wants to light the Bunsen burner, what is the first thing to do;

  1. Light a match/wooden splint and hold it at the gas tap using the rubber tubing.

  2. Close air hole and connect the burner to the gas tap using the rubber tubing.

  3. Open the gas tap slowly to half way to fully open position.

  4. Open the hole slowly



  1. What is the best definition of Brownian motion?

  1. Uniform movement of particles

  2. A motion discovered by Robert Brownian

  3. A random movement of particles of gas and liquid

  4. A random movement of particles of gas and solid



  1. Which of the following is the Latin name of mercury;

  1. Hydragyrum B. Hydrogyrum C. Hydragum D. Hydrorum



  1. The English name of Argentium is;

  1. Gold B. Lead C. Sodium D. Silver



  1. A metal that is usually in liquid form is called;

  1. Mercury B. Bromine C. Iron D. Sulphur



  1. A symbol which represents the substances which can catch fire easily is;

  1. Flammable B. Toxic C. Explosive D. Radioactive



  1. Factors in an experiment that can be manipulated to get desired results are called;

  1. Controlled variables

  2. Uncontrolled variables

  3. Dependent variables

  4. Independent variables



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  1. Write the letter of the best match from column B against a name of the element in column A.

COLUMN A

COLUMN B

  1. Sodium

  2. Potassium

  3. Mercury

  4. Silver

  5. Gold

  6. Chlorine

  7. Helium

  8. Neon

  9. Copper

  10. lead

  1. Pb

  2. L

  3. Na

  4. Au

  5. Cu

  6. Cl

  7. Hg

  8. N

  9. Me

  10. Ag

  11. Co

  12. Ne

  13. He

  14. K

  15. P

  16. S



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SECTION B: 54 MARKS

  1. (a) Why is the chemical symbol of sodium “Na” instead of “S”? ……………………………………………………………………………………………………….

(b) Mention the three rules of assigning symbols to elements

i. ………………………………………………………………………………………………

ii. ……………………………………………………………………………………………….

iii. ………………………………………………………………………………………………



  1. (a) Give the reason to why the chemicals in the laboratory should be labeled and well closed after use. ……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………..

(b) The shelves in the laboratory should be labeled and constructed in a way that it is at the eye level and not above the eye level. Give the reason behind the statement ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………



  1. (a) Write the 6 scientific procedure in a form of descending (from the last to the first) ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(b) There is no solution of a problem without research. Prove the statement. ………………………………………………………………………………………………………………………………………………………………………………………………………………



  1. Fill in the blanks in the below names of the elements;

  1. H_dr_g_r_m

  2. N_ t_ _um

  3. _l_ m _um

  4. _r_ en_ium

  5. Pot_ _ _ium.

  6. B_ r _ _ _ium



  1. (a) What are the effect if on to fails to follow the following laboratory instructions;

  1. Failure to follow instructions guided. …………………………………………………………………………………………..

  2. Improper disposal of broken glass materials ……………………………………………………………………………………………….

(b) Write the functions of the following laboratory tools 2 functions;

Round bottomed flask

i. …………………………………………………………………………………………..

ii. …………………………………………………………………………………………..

Burette

i. ……………………………………………………………………………………….

ii. ……………………………………………………………………………………….



  1. (a) Draw the diagrams of the following warning signs;

  1. Toxic (ii) Flammable (iii) Radioactive













(b) Give the reason to why most of petrol stations and cars have areas written “NO SMOKING”?

……………………...................................................................................................................................................................................................................................................................................................................



  1. (a) Draw a well labelled diagram of a luminous flame;























(b) Mention the regions of non – luminous flame.













  1. (a) What is a compound? Give three examples of a compound. ……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….

  1. What is a mixture? Give five examples of mixture …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….



  1. Write down six properties of a metal;

  1. …………………………………………………………………………………………………

ii. ………………………………………………………………………………………………..

  1. ………………………………………………………………………………………………..

  2. ………………………………………………………………………………………………..

  3. ………………………………………………………………………………………………..

  4. …………………………………………………………………………………………………

  1. Give explanation on how many ways can metal and non metal be differentiated with proper examples and diagram where necessary.























LEARNINGHUBTZ.COM Page 7


TOPIC : 4  MATTER

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

MATTER



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils



SECTION A: 20 MARKS

  1. Choose and write the letter of the best answer in each of the multiples choices in the space provided;



  1. Which one is the correct meaning of first aid kit;

  1. An immediate help given to an accident victim before attending the hospital.

  2. A small box consists of metal tools only.

  3. A bag consists of books and chemicals.

  4. A small box consists of different instruments and chemicals in assisting an accident victim.



  1. What is chemistry?

  1. The branch of science which deals with the study of life

  2. The branch of science which deals with the study of energy, force, mechanics, waves and the structure of atoms and the physical universe.

  3. The branch of science which deals with the study of properties, composition and structure of matter and the changes matter undergo.

  4. The help that one is given before attending to the hospital.



  1. What do you call an instrument which is used in holding chemicals and heating chemicals;

  1. Measuring cylinder

  2. Gas jar

  3. Test tube

  4. Funnel



  1. When one wants to light the Bunsen burner, what is the first thing to do;

  1. Light a match/wooden splint and hold it at the gas tap using the rubber tubing.

  2. Close air hole and connect the burner to the gas tap using the rubber tubing.

  3. Open the gas tap slowly to half way to fully open position.

  4. Open the hole slowly



  1. What is the best definition of Brownian motion?

  1. Uniform movement of particles

  2. A motion discovered by Robert Brownian

  3. A random movement of particles of gas and liquid

  4. A random movement of particles of gas and solid



  1. Which of the following is the Latin name of mercury;

  1. Hydragyrum B. Hydrogyrum C. Hydragum D. Hydrorum



  1. The English name of Argentium is;

  1. Gold B. Lead C. Sodium D. Silver



  1. A metal that is usually in liquid form is called;

  1. Mercury B. Bromine C. Iron D. Sulphur



  1. A symbol which represents the substances which can catch fire easily is;

  1. Flammable B. Toxic C. Explosive D. Radioactive



  1. Factors in an experiment that can be manipulated to get desired results are called;

  1. Controlled variables

  2. Uncontrolled variables

  3. Dependent variables

  4. Independent variables



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  1. Write the letter of the best match from column B against a name of the element in column A.

COLUMN A

COLUMN B

  1. Sodium

  2. Potassium

  3. Mercury

  4. Silver

  5. Gold

  6. Chlorine

  7. Helium

  8. Neon

  9. Copper

  10. lead

  1. Pb

  2. L

  3. Na

  4. Au

  5. Cu

  6. Cl

  7. Hg

  8. N

  9. Me

  10. Ag

  11. Co

  12. Ne

  13. He

  14. K

  15. P

  16. S



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SECTION B: 54 MARKS

  1. (a) Why is the chemical symbol of sodium “Na” instead of “S”? ……………………………………………………………………………………………………….

(b) Mention the three rules of assigning symbols to elements

i. ………………………………………………………………………………………………

ii. ……………………………………………………………………………………………….

iii. ………………………………………………………………………………………………



  1. (a) Give the reason to why the chemicals in the laboratory should be labelled and well closed after use. ……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………..

(b) The shelves in the laboratory should be labelled and constructed in a way that it is at the eye level and not above the eye level. Give the reason behind the statement ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………



  1. (a) Write the 6 scientific procedure in a form of descending (from the last to the first) ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(b) There is no solution of a problem without research. Prove the statement. ………………………………………………………………………………………………………………………………………………………………………………………………………………



  1. Fill in the blanks in the below names of the elements;

  1. H_dr_g_r_m

  2. N_ t_ _um

  3. _l_ m _um

  4. _r_ en_ium

  5. Pot_ _ _ium.

  6. B_ r _ _ _ium



  1. (a) What are the effect if on to fails to follow the following laboratory instructions;

  2. Failure to follow instructions guided. …………………………………………………………………………………………..

  3. Improper disposal of broken glass materials ……………………………………………………………………………………………….

(b) Write the functions of the following laboratory tools 2 functions;

Round bottomed flask

i. …………………………………………………………………………………………..

ii. …………………………………………………………………………………………..

Burette

i. ……………………………………………………………………………………….

ii. ……………………………………………………………………………………….



  1. (a) Draw the diagrams of the following warning signs;

  1. Toxic (ii) Flammable (iii) Radioactive













(b) Give the reason to why most of petrol stations and cars have areas written “NO SMOKING”?

……………………...................................................................................................................................................................................................................................................................................................................



  1. (a) Draw a well labeled diagram of a luminous flame;


(b) Mention the regions of non – luminous flame.

  1. (a) What is a compound? Give three examples of a compound.

  1. What is a mixture? Give five examples of mixture

  1. Write down six properties of a metal;



  1. Give explanation on how many ways can metal and non metal be differentiated with proper examples and diagram where necessary.



LEARNINGHUBTZ.COM Page 5


TOPIC : 5  SEPARATION OF MIXTURES

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

SEPARATION OF MIXTURES



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils


SECTION A:

1. Choose the best option from the choices given below.

(i) When salt is dissolved in water, a uniform mixture is formed. The resulting

mixture is known as;

  1. Solute

  2. Solvent

  3. Heterogeneous mixture

  4. Solution

  5. Suspension


(ii) The second step in scientific procedure is ………………

  1. Data collection and analysis

  2. Conclusion drawing

  3. Formulation of hypothesis

  4. Experimentation and observation

(iii) The following are examples of mixture except;

  1. Milk

  2. Sea water

  3. Ethanol

  4. Human blood

  5. Soda


(iv) The reverse process of vapour changing to solid is known as ………………….

  1. Deposition

  2. Condensation

  3. Freezing

  4. Freezing point


(v) When anhydrous copper(II) sulphate is left on the glass turns blue. This confirms

presence of ………………………. in air;

  1. Carbon dioxide

  2. Dust particles

  3. Water vapour

  4. Noble gases


(vi) Decantation process involve …………………………

  1. Saturation

  2. Sedimentation

  3. Melting

  4. Distillation


(vii) When carbon dioxide gas is passed through the lime water, it turns lime water…….

  1. Blue

  2. Green

  3. Whitish grey

  4. Milk


(viii) The moving solvent in the chromatographic column is called …………………

  1. Mobile phase

  2. Stationery phase

  3. Analyte

  4. Chromatogram


(ix) The method of extracting oil from seed is known as ……………….

  1. Chromatography

  2. Oiling

  3. Solvent extraction

  4. Distillation


(x) When substance is heated and it changes directly from solid to vapour, this process is known as;

    1. Condensation

    2. Deposition

    3. Sublimation

    4. Evaporation


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      1. Match the items in List A with their corresponding responses in List B.

LIST A:

LIST B

  1. Paraffin and water mixture

  2. Iron fillings from sulphur powder.

  3. Iodine and sand.

  4. Rice and sand.

  5. Components of ink.

  6. Rice from chaff.

  7. River water.

  8. Separation of mixture by differences in their boiling points.

  9. Mixture of salt and water.

  10. Liquid obtained after decantation.

  1. Decantate

  2. Deflegration

  3. Filtrates.

  4. Separating funnel

  5. Decantation

  6. Blowing wind

  7. Winnowing

  8. Simple distillation

  9. Deposition

  10. Sublimation

  11. Magnetic method

  12. Chromatogram

  13. Chromatograph

  14. Precipitation

  15. Crystallization

  16. Fractional distillation


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SECTION B:

  1. Supply the suitable word in the space provided;

  1. …………………………… is a mixture of a pure metal with one or more other elements.

  2. Brass is made by mixing ………………. and ……………………

  3. Steel is made by mixing …………………… and …………………………….

  4. A steel with higher contact of iron is called ……………………………

  5. The liquid which mix together completely is known as …………………………


  1. (a) Give three differences between compounds and mixture;

Compound

Mixture

i.


ii.


iii.


i.


ii.


iii

(b) Two differences between solution and suspension

Solution

Suspension

i.


ii.


i.

ii.



  1. Define the following term;

  1. Air ………………………...................................................................................................................................................................................................................................

  2. Saturated solution ………………………………………………………………………………………………………………………………………………………………………………

  3. Unsaturated solution ……………………………………………………………………………………………………………………………………………………………………………..

  4. Super – saturated solution ………………………………………………………………………………………………………………………………………………………………………………


  1. (a) What is distillation ……………………………………………………………………………………………………………………………………………………………………………………

(b) Below is a set up of apparatus and equipments used in fractional distillation, name the parts labeled by letters from A to E.



(c) What is the main use of A in the diagram above? ………………………………….

(d) Give 3 examples of mixtures that can be separated through fractional distillation (i) ……………………………………………………………………………

(ii) …………………………………………………………………………….

(iii) ……………………………………………………………………………..



LEARNINGHUBTZ.COM Page 4


TOPIC : 5  SEPARATION OF MIXTURES

                                                                                                                        LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

SEPARATION OF MIXTURES

 

NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1.    This paper consists of sections A,  and B
  2.    Answer all questions
  3.    All answers must be written in the spaces provided
  4.    All writings should be in blue/black inks except for drawings that should be in pencils

 

SECTION A:

1.  Choose the best option from the choices given below.

 (i) When salt is dissolved in water, a uniform mixture is formed. The resulting  

      mixture is known as;

  1.                   Solute 
  2.                   Solvent
  3.                   Heterogeneous mixture
  4.                  Solution
  5.                   Suspension

 

 (ii) The second step in scientific procedure is ………………

  1.                   Data collection and analysis
  2.                   Conclusion drawing
  3.                   Formulation of hypothesis
  4.                  Experimentation and observation

  (iii) The following are examples of mixture except;

  1.                   Milk
  2.                   Sea water
  3.                   Ethanol
  4.                  Human blood
  5.                   Soda

 

(iv) The reverse process of vapour changing to solid is known as …………………. 

  1.   Deposition
  2.   Condensation
  3.    Freezing
  4.   Freezing point

 

(v) When anhydrous copper(II) sulphate is left on the glass turns blue. This confirms 

       presence of ………………………. in air; 

  1.   Carbon dioxide
  2.   Dust particles
  3.    Water vapour
  4.   Noble gases

 

(vi) Decantation process involve …………………………

  1.           Saturation
  2.             Sedimentation
  3.            Melting
  4.           Distillation

 

(vii) When carbon dioxide gas is passed through the lime water, it turns lime water…….

  1.   Blue
  2.               Green
  3.    Whitish grey
  4.   Milk

 

(viii) The moving solvent in the chromatographic column is called ………………… 

  1.   Mobile phase
  2.   Stationery phase
  3.    Analyte
  4.   Chromatogram

 

(ix) The method of extracting oil from seed is known as ……………….

  1.   Chromatography
  2.   Oiling
  3.    Solvent extraction
  4.   Distillation

 

(x) When substance is heated and it changes directly from solid to vapour, this process is known as;

  1.    Condensation
  2.    Deposition
  3.     Sublimation
  4.    Evaporation

 

i

ii

iii

iv

v

vi

vii

viii

ix

x

 

 

 

 

 

 

 

 

 

 

 

(a)  Match the items in List A with their corresponding responses in List B. 

LIST A:

LIST B

  1.      Paraffin and water mixture
  2.    Iron fillings from sulphur powder.
  3.  Iodine and sand.
  4.  Rice and sand.
  5.    Components of ink.
  6.  Rice from chaff.
  7. River water.
  8.                      Separation of mixture by differences in their boiling points.
  9.  Mixture of salt and water.
  10.    Liquid obtained after decantation.
  1.   Decantate
  2.   Deflegration
  3.    Filtrates.
  4.   Separating funnel
  5.   Decantation
  6.    Blowing wind
  7.   Winnowing 
  8.   Simple distillation
  9.      Deposition
  10.      Sublimation
  11.   Magnetic method
  12.    Chromatogram
  13.  Chromatograph
  14.   Precipitation
  15.   Crystallization
  16.    Fractional distillation

 

i

ii

iii

iv

v

vi

vii

viii

ix

x

 

 

 

 

 

 

 

 

 

 

 

SECTION B:

  1.    Supply the suitable word in the space provided;

(a)  …………………………… is a mixture of a pure metal with one or more other elements. 

(b)  Brass is made by mixing ………………. and ……………………

(c)  Steel is made by mixing …………………… and ……………………………. 

(d) A steel with higher contact of iron is called …………………………… 

(e)  The liquid which mix together completely is known as …………………………

 

  1.    (a) Give three differences between compounds and mixture;

Compound 

Mixture 

i. 

 

ii.

 

iii. 

 

i.

 

ii.

 

iii

(b) Two differences between solution and suspension 

Solution 

Suspension 

i. 

 

ii.

 

i.

ii.

 

 

  1.    Define the following term;

a)     Air ………………………...................................................................................................................................................................................................................................

b)     Saturated solution ………………………………………………………………………………………………………………………………………………………………………………

c)      Unsaturated solution ……………………………………………………………………………………………………………………………………………………………………………..

d)     Super – saturated solution ………………………………………………………………………………………………………………………………………………………………………………

 

e)     (a) What is distillation ……………………………………………………………………………………………………………………………………………………………………………………

(b) Below is a set up of apparatus and equipments used in fractional distillation, name  the parts labeled by letters from A to E. 

 

 

(c) What is the main use of A in the diagram above? ………………………………….

(d) Give  3 examples of mixtures that can be separated through fractional distillation (i) ……………………………………………………………………………

(ii) …………………………………………………………………………….

(iii) ……………………………………………………………………………..

 

LEARNINGHUBTZ.COM Page 1

 

TOPIC : 6  HEAT SOURCES

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

CHEMISTRY LABORATORY



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils



SECTION A:

        1. Choose the best answer from the given statements, and write it in the table provided below;

  1. Which of the following warning signs is likely to appear on a bottle containing concentrated nitric acid in the laboratory?

  1. Corrosive

  2. Explosive

  3. Irritant

  4. Flammable

  1. When a chemist studies a substance h/she is interested in its;

  1. Force of attraction

  2. Properties

  3. Shape

  4. Smell



  1. Certain activities are required in order to manage laboratory techniques and safety. There are;

  1. Laboratory rules to be observed

  2. First Aid to be used

  3. Warning signs and protective symbols to be used

  4. All of the above



  1. What can be the cause of fires in the laboratory;

  1. Exposure of flammables to heat and open fires

  2. Improper treatment of explosive and highly reacting substances

  3. Performing experiments without permission and without protection

  4. All of the above



  1. What might happen to a careless pupil in the laboratory?

  1. He may get injuries

  2. He will not achieve in studies

  3. He will cause loss of things

  4. Nothing will happen



  1. A person who loses too much blood due to an accident is likely to go into;

  1. Burns

  2. Shock

  3. Sores in his/her mouth

  4. Painful wounds



  1. Which one of the following statement does not show that chemistry knowledge has been applied?

  1. Rock and earthly materials are changed to iron and steel

  2. We obtain processed food stuffs and drinks from industries

  3. Pharmaceutical works provide with various types of medicine

  4. We can enjoy music produced by the best singer



  1. A booklet containing guidelines for first Aid is a;

  1. Chemistry book

  2. First kit

  3. First Aid manual

  4. First Aid component



  1. A form one student found a bottle with a sign of a skull and crossed bones. The sign means;

  1. Toxic

  2. Irritant

  3. Flammable

  4. Explosive



  1. Which of the following is not among the instruments and chemicals used for First Aid?

  1. Pair of scissors

  2. Mosquito net spray

  3. Assorted bandages

  4. Sterilized cotton wool

i

ii

iii

iv

v

vi

vii

viii

ix

x













2. Match the items of column B to those of column A for meaningful statements and enter the answers in the table provided below;



COLUMN A:

  1. Gas poisoning

  2. A laboratory rule

  3. Usually applied on fresh wounds and bruises

  4. Used to protect the clothes of a caregiver against dirt and fluids such as blood, pus from the patient or victim.

  5. Explosion

  6. A measure taken to protect people or things against possible harm or trouble

  7. Fertilizers, drugs, detergents

  8. Can poison you and can cause immediate death

  9. Apparatus

  10. Symbol for magnesium element



COLUMN B:

  1. Apron

  2. No fume chamber

  3. Oral ingestion

  4. Chemistry application

  5. Things which are used to carry out experiments in the laboratory

  6. Iodine tincture

  7. Pain killers

  8. Precautions

  9. Toxic

  10. Mg

  11. Corrosive

  12. Be calm and silent

  13. A forceful rapid reaction which involved throwing off particles at high speed and releasing energy such as heart and loud sounds.

  14. Mn

  15. History

  16. Harmful

i

ii

iii

iv

v

vi

vii

viii

ix

x













SECTION B:

Answer these questions only shortly and briefly.



  1. (a) Write TRUE for a correct statement and FALSE for a false statement, in the

Following;

  1. The hazard label for petrol is normally flammable sign which means catches fire easily ……………..

  2. Fuels and chemicals such as plastics, pesticides, perfumes, detergents are the products made from soil and natural gas. ……………….

  3. A form one student found a bottle with a sign of a skull and crossed bones. The sign means explosion. ………………

  4. Never keep toxic materials in children’s’ reach areas since they may poison them ……………..

  5. Experiments in which poisonous gases and vapour are produced, must not be carried out in a fume chamber. ……………………

  6. A school laboratory should always be clean and well arranged ………………



  1. What is the purpose of doing experiments in the learning of chemistry? ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

  2. (a) What is the aim of using warning sign on containers in the chemistry laboratory? ………………………………………………………………………………………………………………………………………………………………………………………………

(b) Name one example of a protective symbol ………………………………………………………………………………………………



  1. In the space below, draw clear and neat warning signs found on containers

  1. Corrosive (iii) Explosive



  1. High flammable/ inflammable

  1. Write name of one chemicals under each of the following

  1. Oxidant/oxidizing agent ……………………………………………………………

  2. Toxic/poison …………………………………………………………………………

  3. Harmful/ irritant ……………………………………………………………………...



  1. Draw the following warning signs

  1. oxidant (b) flammable



  1. State three areas where chemistry knowledge is applied in day to day life; and give TWO examples in each area.

Area

Example

i.


ii.


iii.








  1. Complete the following table;



FIRST AID KIT

  1. A pair of scissors

Diagrams

Quantity

Used for

How used


1


Measuring body temperature.


  1. Sterilized cotton wool












1 reel

Washing












  1. Name six injuries which can be caused by running in the laboratories or in the corridor of it.

  1. ……………………………………………………………….

  2. ………………………………………………………………..

  3. ………………………………………………………………..

  4. ………………………………………………………………..

  5. ……………………………………………………………….

  6. ………………………………………………………………..









SECTION C:

Include only the necessary points in answering the following questions.



  1. How can you help a fellow student who has been injured by a chemical splash into his/her eyes?



  1. As a safety measure it is stated that “wear protective equipments when doing dangerous experiments”. How you can explain this



LEARNINGHUBTZ.COM Page 5


TOPIC : 6  HEAT SOURCES AND FLAMES

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

HEAT SOURCES AND FLAME



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils

1. MULTIPLE CHOICE QUESTIONS

(i) Why is the non-luminous flame best for laboratory work?

  1. It is easily produced

  2. It roars

  3. It is non-sooty, very hot and steady

  4. It is not small.

(ii) Which part of the Bunsen burner keeps it upright with enough stability?

  1. Chimney

  2. Metal collar

  3. Heavy metal base

  4. Air holes

(iii) What can be the course of fires in the laboratory?

  1. Exposure of flammables to heat and open fires

  2. Improper treatment of explosive and highly reacting substances

  3. Performing experiments without permission and without protection

  4. All of the above.

  1. Which of the following is unlikely to produce soot?

  1. Luminous flame B. Candle C. Stove D. Non luminous flame



  1. What is usually found in the chimney of a Bunsen burner when it is on use

  1. Oxygen

  2. The fuel gas

  3. A mixture of oxygen and the flammable

  4. Non of the above

  1. A Bunsen burner flame will produce luminous flame when;

  1. Gas tap is fully opened

  2. Air holes of Bunsen burner is fully closed

  3. Air holes of Bunsen burner is fully opened

  4. Sufficient gas is supplied to the burner

  1. The non – luminous flame is formed when;

  1. The air holes of the Bunsen burner are closed

  2. The air holes of the Bunsen burner are open

  3. The Bunsen burner is outside the laboratory

  4. The Bunsen burner is inside the laboratory

  1. The Bunsen burner is likely to contain soot when;

  1. The air hole is closed

  2. The air hole is open but not fully

  3. The air holes of Bunsen burner are completely open.

  4. The burner is not raised

  5. The gas supply is high

  1. In most general sense the word combustion means …………….

  1. Burning substance in oxygen or air.

  2. Burning compound of carbon in air.

  3. Burning any fuel in air or oxygen

  4. By chemical combination accompanied by light and heat in which or more reactants is gaseous



  1. 10 grams of copper powder were placed initiation tube containing air. The tube was very strongly for half an hour. At the end experiment;

  1. Copper increased in mass in changed colour

  2. Copper melted into liquid copper form.

  3. The total mass of tube and its content decreased.

  4. Water vapour appeared in the tube.



  1. Match the following items by writing the letter of the best match against a number in the space provided;

COLUMN A

COLUMN B

  1. Blue flame

  2. Hottest part of a Bunsen flame

  3. Heavy metal base

  4. Spirit burner

  5. A roaring flame

  6. Rubber tube

  7. Unburnt gas/ dark zone

  8. Barrel

  9. Burning takes place at the surface of combustible material






  1. Sulphur head at the base of a Bunsen flame is not ignited.

  2. Gas from a glass tube at the bottom of Bunsen flame can be ignited.

  3. For stability of a Bunsen flame.

  4. For holding a gas tube.

  5. Leads gas from gas tube to the small jet.

  6. Leads gas from gas cylinder to the gas tube.

  7. Air holes of Bunsen burner are closed.

  8. Burning of gas is complete.

  9. Card placed horizontally at the top of flames.

  10. Card placed vertically at the top of flames.

  11. 300° C of a blue flame.

  12. 1540°C of a blue flame

  13. Produces a ring shape burn of a card.

  14. The tip of the blue – green middle zone of flame.

  15. Alternative source of heat in the laboratory.

  16. Wick of burner should not dry up.

  17. Also called chimney.

  18. Also called metal collar/ ring.

  19. My strike back

  20. May be silent on the basis of the gas flow.







SECTION B



  1. (a) What is a flame?

(b) Write five differences between a luminous flame and a non luminous flame

(c) Draw a well labeled diagram of a luminous flame

(d) Draw a well labeled diagram of a non luminous flame

(e) Mention two advantages of a Bunsen burner over other sources of heat in the laboratory

  1. Explain why spirit lamp, kerosene stove, gas stove and Bunsen burner can be used as heat sources in the laboratory. ................................................................................................................................................................................................................................................................................................................................................................................................................................................

  2. (a) Briefly explain any five methods of preventing rusting.

  1. ………………………………………………………………………………………………………………………………………………………………………………

  2. ………………………………………………………………………………………………………………………………………………………………………………

  3. ………………………………………………………………………………………………………………………………………………………………………………

  4. ………………………………………………………………………………………………………………………………………………………………………………

  5. ………………………………………………………………………………………………………………………………………………………………………………

(b) A certain pink coloured compound is heated to form blue colour. When water is
added to sample , it changed back to pink.

i. What change is demonstrated by the compound …………………………………....

ii. Explain the reasons for your choice.

…………………………………………………………………………………………………………………………………………………………………………………………...….

(c) State the type of changes demonstrated by the following phenomenon;

  1. Burning of firewood ……………………………………………………….

  2. Rotting of meat …………………………………………………………….

  3. Heating frying pan …………………………………………………………..

  4. Melting of butterfat …………………………………………………………

  5. Change of cloud to rain ……………………………………………………..

  6. Heating of iron rod ………………………………………………………….


6. (i) Give two similarities between combustion and rusting …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(ii) Give two differences between combustion and rusting …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

  1. (a) What is fire?

(b) State three (3) necessary conditions to be satisfied for a fire to start or to continue.

(c ) For each of the following classes of fire, state its appropriate fire extinguisher(s)

  1. Class A – fires

  2. Class B – fires

  3. Class C – fires

  4. Class D – fires

  5. Class E – fires

  1. (a) For each of the following classes of fire, state the burning material(s);

  1. Class A fire ……………………………………………………………………………………………

  2. Class B fire ……………………………………………………………………………………………

  3. Class C fire ……………………………………………………………………………………………

(b) Fire can be prevented by;

  1. …………………………………………………………………………………………………………

  2. …………………………………………………………………………………………………………

  3. ……………………………………………………………………………………………………………………………………………………………………………

  1. In an experiment to determine the percentage of oxygen in air using a white phosphorous, Juma inverted measuring cylinder in a trough of water and he attached of small piece of white phosphorous to the end of piece of piece of wire and placed in the measuring

  • He then left set up over night;



  1. State precaution during this experiment; ………………………………………………………………………………………………………………………………………………………...................................... 01 marks.

  2. Explain observation made ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………… 02 marks

  3. Why yellow/white phosphorous is stored under water. …………………………………………………………………………………………………………………………………………………………………………………. 1 ½ marks

Illustrate your result using clear well labeled diagram.

  1. (a) Which gas in the atmosphere is inert and so prevents the earth from been set to fire?

Answer: ______________________________________________________________

Which is the active component of the air?

Answer: _____________________________________________________________

(b) Write C for a combustion reaction and B for only burning reaction against the following:

(i) Carbon + oxygen → carbon dioxide _______________________

(ii) Copper + chlorine  copper (II) chloride __________________________

(iii) Sodium + nitrogen → sodium nitride __________



LEARNINGHUBTZ.COM Page 5


TOPIC : 7  AIR, COMBUSTION, RUSTING AND FIRE FIGHTING

LEARNING HUB.TZ

CHEMISTRY EXAMINATION FORM ONE

TOPICAL EXAMINATIONS.

AIR COMBUSTION, FIRE FIGHTING AND RUSTING



NAME………………………………………..CLASS…………………………………………….……………TIME: 21/2HRS

INSTRUCTIONS:-

  1. This paper consists of sections A, and B

  2. Answer all questions

  3. All answers must be written in the spaces provided

  4. All writings should be in blue/black inks except for drawings that should be in pencils

  5. Multiple choice Questions.

  1. When anhydrous copper (II) sulphate is left on the glass turns blue. This confirms

Presence of …… in air;

  1. Carbon dioxide

  2. Dust particles

  3. Water vapour

  4. Noble gases

  1. What type of fire occurs in the vapour air mixture over the surface of flammable liquid?

  1. Class A B. Class B C. Class C D. Class D.

  1. Under normal conditions approximately what percentage of air is oxygen?

7.8% B. 21% C. 78% D. 0.03%

  1. What type of fire is associated with electrical equipment?

  1. Class A. B. Class C C. Class E D. Class F.

  1. The properties like colorless, highly flammable and the use for manufacturing ammonia would specifically be for a certain gas. Which one is it?

  1. Methane B. Oxygen C. Hydrogen D. Carbon dioxide



  1. What can be the course of fires in the laboratory?

  1. Exposure of flammables to heat and open fires

  2. Improper treatment of explosive and highly reacting substances

  3. Performing experiments without permission and without protection

  4. All of the above.

  1. If a heap of organic materials like timber paper and firewood catches fire which extinguishers will be the best to stop the fire :-

  1. Carbon dioxide

  2. Water

  3. Foam

  4. Sand

  1. Domestic utensils made of iron undergo rusting when exposed to;

A. Air and fire B. Air and oil C. Air and water D. Water and oil

  1. What real takes place during sacrificial protection of iron from rusting?

  1. The reactive metal remains uncorroded

  2. The reactive metal is corroded

  3. The reactive metal and iron are corroded

  4. The iron is corroded


  1. What is kindling temperature

  1. A kind temperature

  2. Temperature out of a burning material

  3. The highest temperature obtained from a burning substance

  4. The lowest temperature at which a combustible material can catch fire.



  1. Match the following items by writing the letter of the best match against a number in the table below;



COLUMN A

COLUMN B

  1. Air is not a compound

  2. Krypton

  3. Carbon dioxide in air

  4. Burning


  1. Pass

  2. Iron (II) oxide + water rust.

  3. Oiling and painting.

  4. Presence of the three components of the fire triangle.

  5. Kindling temperature


  1. Hydrogen + oxygen water

  2. Hydrogen + chlorine Hydrogen chloride

  3. Stages used in fire control

  4. Fire preventive measures.

  5. Class A fire

  6. Metal fires

  7. First stage reaction in forming rust.

  8. Second stage reaction in forming rust.

  9. Air has no simple chemical formula to represent it.

  10. Separated by physical process.

  11. Percentage volume composition in the air is 0.00001.

  12. Percentage volume composition in the air is 0.0001.

  13. Prevent rusting of iron temporarily.

  14. Prevents rusting of iron permanently.

  15. Fire erupts.

  16. Use A.P. W.

  17. The lowest temperature at which a combustible material can catch fire.

  18. Temperature below initiation point.

  19. Forms white crust on lime water in a beaker left open for some days.

  20. Changes lime water milky.





  1. Write down 6 methods which can be used to prevent rusting. Begin with the most effective to the least effective.

  2. (a) Which property of hydrogen leads to the following uses of it?



Use

Property


  1. Oxy – hydrogen flame

  2. Weather balloons

  3. Manufacture of margarine


……………………………………………………….

………………………………………………………..

……………………………………………………….




(b) Which property of oxygen leads to the following uses of it?

Use

Property


  1. Plants and animals

  2. Metal cutting and welding

  3. Removal of impurities


……………………………………………………….

………………………………………………………..

……………………………………………………….




  1. A) Define the term class B fire.

b) i) Mention two combustible materials in class B fire

ii) Why is water not used to put off oily fires?

iii) Your friends clothes have caught fire. In order to extinguish the fire, you have decided to cover her with a blanket. What is the function of the damp blanket?

c) i) Why is air a mixture and not a compound?

ii) Why is rusting of iron a chemical change?

  1. A) i) State two conditions required for rusting to take place

ii) List two methods which are used to prevent iron from rusting

b) State three properties that makes aluminium useful in overhead cables.

7. a) What is fire triangle? Explain using a diagram

b) Explain three ways of preventing fire from occurring at home.

8. a) Briefly explain the following,

i) Iron left outside for some time will have a brown colour.

ii) Things made of iron rust faster at the coast than at upcountry areas.

iii) When carbon dioxide is passed through lime water for some times, the limewater turns milky.

9. Briefly explain how the following methods can be used to prevent rusting?

i) Sacrificial method

ii) Painting

iii) Galvanizing

iv) Coating

v) Electroplating

10. a) Briefly explain how you can test for the following gases

i) Oxygen gas

ii) Carbon dioxide

iii) Water vapour

b) State two uses of the following gases

i) Nitrogen gas.

ii) Oxygen gas

iii) Carbon dioxide gas.



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