2. Answer all questions in section A and B. Answer ONE question from section C
3. All answer should be written in the answer sheet(s) provided.
4. Cellular phones and any unauthorized materials are not allowed in the examination room
5. Write your name/candidate number on every page of your answer sheet(s)
SECTION A (15 MARKS)
Answer all questions in this section
1. For each of the item (i) – (x) choose the correct answer from among the given alternatives and write
its letter beside the item number
i. Chemistry is defined as:
A. The scientific study of matter, compound and chemical reactions
B. The scientific study of compounds, mixture and organic substances
C. The scientific study of composition, structure and properties of matter
D. The study of relation between human being, medicine and pollution
ii. Why is water a universal solvent?
A. It is neither acidic nor basic than any other known liquid.
B. It dissolves more substances than any other known liquid
C. It occurs naturally in all the three states of matter than any other liquid
D. It dissolves both organic and inorganic solutes than any other liquid
iii. Technicians prefer to use blue flame in welding because
A. It is bright and non-sooty
B. It is light and non-sooty
C. It is very hot and large
D. It is very hot and non-sooty
iv. All 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
v. An important property of oxygen which distinguishes it from other gases is that it:
A. Supports combustion but does not burn
B. Burns and support combustion
C. Burns but does not support combustion
D. Neither burns nor support combustion
vi. The choice of the source of heat depends on the:
A. Colour of the flame
B. Quantity of heat produced
C. Substance to be burned or boiled
D. Type and shape of flame
vii. Which state is involved when drying wet clothes?
A. Liquid to solid
B. Solid to gas
C. Gas to liquid
D. Liquid to gas
viii. Your friends were arguing about the scientific procedure that follows after experimentation. Which stage will you suggest your friends?
A. Hypothesis
B. Data interpretation
C. Data collection
D. Experimentation
ix.The flame which is generally used in the laboratory is the one with:
A. two zones.
B. four zones.
C. one zone.
D. three zones
x.The branch of chemistry that deals with the study of carbon and its associated compound is called?
(a) Physical chemistry
(b) Analytical chemistry
(c) Organic chemistry
(d) Inorganic chemistry
2.(a) Match the items in List A with a correct response in List B by writing the letter of the correct response below the corresponding item number in the table provided .
SECTION B (70 MARK)
Answer all question in this section
(a) Define the term laboratory safety……………………………………………………………………………….
………………………………………………………………………………………………………………………
(b) Laboratory safety measures are very important and should be considered for accurate laboratory works, as a form one student briefly state the important of the following measures during scientific experiments.
(i) Cupboards, storage cabinets and drawers should have locks
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
(ii) Refrigerators and freezers used should be labeled for chemical use only
………………………………………………………………………………………………………………………
(iii) If there is a smoke to the extent of not being able to access the exist, it is advised to lie on the floor while searching for exist points
………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
(iv) The laboratory should be well ventilated and door should open outward
(c). Bleeding is the loss of blood and other fluids from the body when the skin breaks. As a form two student identify procedures when dealing with a victim of a small cut or wound.
4. You are provided with the following diagram below, study it carefully and answer the question that follows;
(a) (i) Give sort and clear description about what will be observed in each beaker A – D after 2 or 3 days
In beaker
A…………………………………………………………………………………………………
……………………………………………………………………………………………………
In beaker
B…………………………………………………………………………………………………
……………………………………………………………………………………………………
In beaker
C…………………………………………………………………………………………………
……………………………………………………………………………………………………
In beaker
D…………………………………………………………………………………………………
……………………………………………………………………………………………………
(ii) What is the aim of experiment set up in above diagram?.........................................................
……………………………………………………………………………………………………
(iii) Write one effect of the process taken in the experiment above in our daily life activities.
……………………………………………………………………………………………………
(b) Briefly explain why corrugated iron sheet at coastal region like Dar es Salaam rust very fast compared to that at central regions like Dodoma?
……………………………………………………………………………………………………
……………………………………………………………………………………………………
(c) Some metals such as aluminum, lead and zinc do not rust easily, explain why
……………………………………………………………………………………………………
……………………………………………………………………………………………………
5.(a) Explain the following phenomena based on the idea of particles:
(i) It is easy to pour a liquid………………………………………………………………………….
……………………………………………………………………………………………………………
……………………………………………………………………………………………………………
(ii). A gas will completely fill any container…………………………………………………………..
……………………………………………………………………………………………………………
……………………………………………………………………………………………………………
(iii). A solid expands when heated…………………………………………………………..................
…………………………………………………………………………………………..…………………
……………………………………………………………………………………………………………
(b) Magebo placed a large crystal of potassium permanganate in the bottom of the beaker of cold water in chemistry laboratory and left it for several hours, according to kinetic theory of matter briefly explain about the following;
(i) What she must have observed after five minutes…………………………………………
……………………………………………………………………………………………
(ii) What she likely to observed after several hours…………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
…………………………………………………………………………………………....
(iii) Name the two process which have taken place?................................................................
……………………………………………………………………………………………
………………………………………..
(iv) From that experiment give conclusion about matter………………………………………
……………………………………………………………………………………………
…………………………………………………………………………………………….
(c) State the principle of kinetic theory of matter……………………………………………………
……………………………………………………………………………………………………
……………………………………………………………………………………………………
6.(a) Draw a well labeled diagram of a small laboratory heat source consisting of vertical metal tube connected to a gas source.
(b) Describe how you will light a device drawn above
i)……………………………………………………………………………………………………
……………………………………………………………………………………………………...
ii)…………………………………………………………………………………………………..
…………………………………………………………………………………………………….
iii)…………………………………………………………………………………………………..
iv)…………………………………………………………………………………………………..
……………………………………………………………………………………………………..
v)…………………………………………………………………………………………………..
(c ) Burning back of the device drawn above is corrected as follows
i)…………………………………………………………………………………………………….
ii)……………………………………………………………………………………………………
iii)…………………………………………………………………………………………………..
7 (a) Chemistry is not an isolated discipline, with vivid example s explain this statement by providing five points.
(i)………………………………………………………………………………………………...
………………………………………………………………………………………………...
………………………………………………………………………………………………...
(ii)………………………………………………………………………………………………..
………………………………………………………………………………………………...
………………………………………………………………………………………………...
(iii)………………………………………………………………………………………………
………………………………………………………………………………………………..
……………………………………………………………………………………………….
(iv)………………………………………………………………………………………………
………………………………………………………………………………………………..
………………………………………………………………………………………………..
(v)………………………………………………………………………………………………
……………………………………………………………………………………………….
……………………………………………………………………………………………….
(b) Use the relevant examples to state about the following statement.
(i) Agriculture and chemical industry can work together………………………………………………
……………………………………………………………………………………………………………
……………………………………………………………………………………………………………
(ii) Chemistry has contributed to environmental hazards………………………………………………
…………………………………………………………………………………………………………..
…………………………………………………………………………………………………………..
(c).i) Who is alchemist?....................................................................................................................
…………………………………………………………………………………………………….
ii) Mention two interest of alchemist…………………………………………………………..
……………………………………………………………………………………………………
……………………………………………………………………………………………………
8. (a) What is laboratory apparatus?..................................................................................................
(b) Blessing was asked by the teacher to go to wash the apparatus in the chemistry laboratory. When she goes there, she was surprised to see the most of apparatus are made up of glass. She was bit confused why it’s like this. You as educated student briefly outlines five disadvantages of using glass materials in chemistry laboratory.
(i)…………………………………………………………………………………………………
(ii)…………………………………………………………………………………………………
(iii)…………………………………………………………………………………………………
(iv)…………………………………………………………………………………………………
(v)………………………………………………………………………………………………
(c) Draw a well, smart diagram of the following laboratory apparatus and give one function for each
9.(a) a) Differentiate first aid from first aid kit……………………………………………………………..
………………………………………………………………………………………………………………….
………………………………………………………………………………………………………………......
b) Mr. Machela got a car accident and was badly injured. During the first aid process, Mr. Zakayo put on gloves, took a bandage and gave him pain killers. What was the use of:-
i. Glove: ……………………………………………………………………………………………….
ii. Bandage: ………………………………………………………………………………………………..
iii. Painkillers: ………………………………………………………………………………………….
c) Explain any five possible causes of an accidents in school chemistry laboratory
i. …………………………………………………………………………………………………………
………………………………………………………………………………………………
ii. …………………………………………………………………………………………………………
………………………………………………………………………………………………
iii. …………………………………………………………………………………………………………
………………………………………………………………………………………………
iv. …………………………………………………………………………………………………………
………………………………………………………………………………………………
v. …………………………………………………………………………………………………………
………………………………………………………………………………………………
SECTION C (15 MARKS)
Answer question number 10 from this section.
10. (a) Form one students reads a statement from a certain book that “If the clothes worn by your friend catch fire, cover them with fire blanket”
(i) What materials composes the fire blanket?
…………………………………………………………………………………………………………………….
(ii)Why fire blanket is to be used in that case?
…………………………………………………………………………………………………………………….
(iii) Briefly explain how it is used to put off the fire
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………
(iv). What type of class of fire occurred to the clothes? Explain your choice
………………………………………………………………………………………………………………………
(b) Outlines general five safety precautions you have to keep in mind when using fire extinguishers;
(i)……………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………
(ii)………………………………………………………………………………………………………………….
………………………………………………………………………………………………………………………
(iii)………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………...
(iv)…………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………
(v)…………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………
(c). State the chemical composition of the extinguishing agent of each of the following portable fire extinguishers;
(i) Dry chemical fire extinguisher……………………………………………………………………………..
(ii) Carbon dioxide fire extinguisher…………………………………………………………………………..
(iii) Wet chemical extinguisher………………………………………………………………………………..
(iv). ABC fire extinguisher…………………………………………………………………………………….
(v). Halon fire extinguisher…………………………………………………………………………………….
(vi). Foam fire extinguisher……………………………………………………………………………………
Thus paper consists of section A, B and C with total of ten (10) questions
Answer all questions
All writing must be in blue or Black in except drawing which must be in pencil
Section A and C carry fifteen (15) marks
Cellular phones and any unauthorized material are not allowed in assessment room
SECTION A
Answer ALL questions.
i. Which is not an importance of studying chemistry;
Understand how matter undergo chemical change
Make various medical products
Understand the use of chemicals in agriculture
Help us enter into various careers.
ii. A mother at home can apply chemistry to;
Weed flowers in the garden
Dusting the floor of her house
Weighing maize flour
Cooking food in the kitchen
iii. What real takes place during sacrificial protection of iron from rusting?
The reactive metal remains uncorroded
The reactive metal is corroded
The reactive metal and iron are corroded
The iron is corroded
iv. Which of the following warning signs is likely to appear on a bottle containing concentrated nitric acid in the laboratory?
Corrosive
Explosive
Irritant
Flammable
v. What is the best definition of Brownian motion?
Uniform movement of particles
A motion discovered by Robert Brownian
A random movement of particles of gas and liquid
A random movement of particles of gas and solid
vi. What is usually found in the chimney of a Bunsen burner when it is on use
Oxygen
The fuel gas
A mixture of oxygen and the flammable
Non of the above
vii. A Bunsen burner flame will produce luminous flame when;
Gas tap is fully opened
Air holes of Bunsen burner is fully closed
Air holes of Bunsen burner is fully opened
Sufficient gas is supplied to the burner
viii. A metal that is usually in liquid form is called;
Mercury
B. Bromine
C. Iron
D. Sulphur
ix. A symbol which represents the substances which can catch fire easily is;
Flammable
B. Toxic
C. Explosive
D. Radioactive
x. When anhydrous copper(II) sulphate is left on the glass turns blue. This confirms presence of ………………………. in air;
Carbon dioxide
Dust particles
Water vapour
Noble gases
Write the letter of the best match from column B against a name of the element in column A.
COLUMN A
COLUMN B
Sodium
Potassium
Mercury
Silver
Gold
lead
Pb
L
Na
Au
Cu
Cl
Hg
N
Me
Ag
Co
Ne
He
K
P
S
SECTION B
(a) What is the aim of using warning sign on containers in the chemistry laboratory?
(b) Name one example of a protective symbol
Write name of one chemicals under each of the following
Oxidant/oxidizing agent
Toxic/poison
Harmful/ irritant
4. (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
5. (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.
6. Define the following term;
Air
Saturated solution
Unsaturated solution
Super – saturated solution
(a) What is distillation
7. (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
8. 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?
9. 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.
SECTION C
10. (a) What are the effect if on to fails to follow the following laboratory instructions;
Failure to follow instructions guided.
Improper disposal of broken glass materials ……………………………………………………………………………………………….
(d) Write the functions of the following laboratory tools 2 functions;
Thus paper consists of section A, B and C with total of ten (10) questions
Answer all questions
All writing must be in blue or Black in except drawing which must be in pencil
Section A and C carry fifteen (15) marks
Cellular phones and any unauthorized material are not allowed in assessment room
SECTION A
For each of items (i) – (x) choose the correct answer from among the given alternatives and write its letter in box provided.
When a chemistry studies a substance, he/she is interested in its
Force of Attraction
Shape
Smell
properties
Chemistry is one of the science which deals with,
alkalinity and Basiaty of substance
the study of cells
composition, properties and behavior of matter
chemical changes
Which of the following illustrates a chemical reaction taking place in our body
Falling sick
Digestion
Respiration
Salvation
Monica found a bottle with chemical which has a source of Oxygen, what warning sign is vicety to be found on it?
Flammable
Explosive
Oxidizing
Corrosive
Which best idea can you have about Uranium, Radon, and carbon – 14
Neither radioactive nor carcinogenic materials
Radioactive and carcinogenic materials
Radioactive but not carcinogenic materials
Non-radioactive carcinogenic material
Kipps apparatus in used in laboratory for
Obtaining continuous supply of gas
Separation of gases
Drying gases
Obtaining Pure gases
A solution is formed when
A solvent is dissolved in a solute
A solute is dissolved in a solvent
A mixture is dissolved in a solvent
Water dissolved crystals
Point out the odd mom out in the following groups of elements
Zinc, sulphur, sodium
Copper sodium, Iron
Alluminium, sodium, Zinc
Sodium, zinc copper
Separation of the constituents of a mixture by fractional distillation is possible when constituents in the mixture differ in their
Boiling point
Solubility
Melting point
Freezing point
The process used to separate a mixture of salt and water is
Evaporation
Filtration
Simple distillation
sublimation
Match each item in LIST A with a correct response in LIST B by writing its letter below the number of the corresponding item in table provided.
LIST A
LIST B
Torch
Bandage
Safety pin
Disposable sterile gloves
Pain killer
Covering hands to contact with victim’s body fluids
Relieving pain
Keeping dressing in place and immobilizing injured limbs
Killing insects
Source of light
Covering wounds to protect them dirt and germs
Source of heat
Reducing Muscle pain
Securing Bandages
Covering the hand to avoid infecting wound
SECTION B (70 MARKS)
Answer all questions from this section
(a)The material resulting from condensation is called condensate. Derive process resulting from following material
Distillate______
Filtrate ____
Sublimate _____
(b)Write the proper method of separating mixtures against each of the following substances
Oil in seed
Sand mixed with iodine crystal
Alcohol mixed with water
Mixture of salt and milk
(a) Give best term that fits description below,
John gave a tentative explanation of why iron rusts when exposed in air
Mary followed, all steps required in carrying out scientific investigation
Juma used a region of burning gas to heat in laboratory
(b)What benefits can Salma gain by studying chemistry? Give four
(a)Write two examples of each of the following
Heterogeneous mixture
Homogeneous mixture
Compound
(b)State the method used to separate the following mixtures and retain their components
Muddy water
Common salt
Oil and water
Ink
(a)Supply the suitable word in space provided
_______ is a mixture of pure metal with another element
Brass is made by mixing __________ and _______
Steel in made by mixing ___________ and ___________
A steel with high content of iron is called _________
Liquid which mix together completely are called __________
(b) Define the following terms
Air
Saturated solution
Unsaturated solution
(a)Write chemical symbols of the following chemical names of elements
Copper
Sodium
Zinc
Aluminum
Iron
(b)Write chemical names of the following chemical symbols of elements
S ________
H ________
O _______
N _______
Cl _______
(a)Write five differences between luminous and Non-Luminous flame
(b)State advantages of Bunsen burner as sources of heat
(a)Explain the following
Laboratory doors should open outwards
Laboratory should have large windows and doors
Laboratory should have fume chambers
Laboratory should have water supply system
(b)State two causes of accident in laboratory
(a)Define the following terms
(i) First Aid (ii) First Aid Kit
(b) Each student required to learns the basics of first aid for helping accident victims. What are the importances of helping accident victims? Four reasons
(c)Shock is a condition in which the body system is unable to take enough blood to the vital Organs Explain the procedures to follow in giving help for a shock victim
This paper consists of sections A and B with a total of TEN (10) questions
Answer all questions in the space provided.
All writing must be in black or blue ink except for diagrams which must be in pencil
Cellular phones and any unauthorized materials are not allowed in the examination room
Write your Examination Number on every page of your answer booklet(s)
The following constants may be used
Zn= 65, X =32, O=16
SECTION A (15 Marks)
Answer all questions in this section
For each of the items (i) - (x), choose the correct answer from among the given alternatives and write its letter beside the item number in the bracket provided.
The substance that can burn your skin is best described as: -
Corrosive
Explosive
Flammable
Toxic
Oxidant
When burette is used in the laboratory its calibration starts from above because.
It measures the volume of remained
It measures the used volume
It measures the volume added
It measures the volume of base added
When burning a fuel produces blue color it means there is
Adequate supply of oxygen with production of soot
In adequate supply of oxygen with production of soot
Adequate supply of oxygen with production of less heat
Adequate supply of oxygen with production of more heat
One of the following apparatus is used to measure fixed volume of liquid
Burette
Pipette
Conical flask
Measuring cylinder
Volumetric flask
What should be done if the results obtained from an experiment do not support the hypothesis?
The results should be left out
A new problem should be identified
The experiment should be changed
Ideas for further testing to find a solution should be given
The hypothesis should be accepted
Water exists in three forms, which are solid, liquid and vapour. Which among of the following are examples of liquid form of water
Rain, snow and hail
Dew, rain and ice
Mist, steam and clouds
Rain, hail, ice
Rain, mist, and dew
Emulsion is the mixture of liquids that do not completely mix with each other.
Which of the following set represent emulsion?
Butter, lotion, toothpaste and milk
Milk, gel, foam, sponge
Cream, gel, lotion and paint
Sponge, milk, smoke, insecticides
Smoke, milk, paint and body spray
Domestic utensils made up of iron do rust as a result of the presence of
Air and fire
Water and oil
Air and water
Air and oil
Water and fire
When Mr Mwendakwao took Glucose and dissolved in water to form a uniform mixture.
water is solution, glucose is solvent and the product is solute
water is solute, glucose is solvent and the product is solution
water is solvent, glucose is solute and the product is solution
water and glucose forms immiscible mixture
water and glucose form emulsion
A simple proof that some chemical reactions take place in our bodies is that
A. We eat a balanced diet
B. Doctors tell us so in the hospitals
C. We occasionally fall sick
D. The food we eat or the drinks we take are quite different from the waste products from our bodies
E. There is no proof
2. Match the items inList Awith the responses inList Bby writing the letter of the correct response beside the item number in the answer sheet or booklet provided.
List A
List B
When air is pumped into test tube contain lime water, lime water turns milky
Condition for iron to rust
Oxygen, Heat and Fuel
Coating of Iron or steel with Zinc
Flammable liquids like petrol, alcohol and kerosene
A. Water is used for extinguishing
B. Oxygen and water/moisture
C. Presence of Oxygen
D. Fire triangle
E. Presence of carbon dioxide
F. Rusting
G. Galvanization
H. Class B fire
I. Nitrogen
SECTION B (70 MARKS)
ANSWER ALL QUESTIONS
3. (a) Consider the diagram below;
(i) Give aim of the above process
(ii) Identify the process A to F
(iii) Give two importance of the above diagram to our daily life.
(b) State whether the following is permanent change or temporary change,
(i) Dissolution of salt in water
(ii) Rotting of mangoes
4. (a) In which other areas do we find the warning signs out of laboratory (give four point)
(b) Explain how measurements of volume differ when using measuring cylinder and burette
(c) It is recommend that laboratory apparatus should be properly washed or wiped after use, explain the significance for this when
Measuring volume of liquids
Measuring mass of substance
5(a) Fill the blanks
The techniques used to separate serum from blood samples is called _________________________
The insoluble substances remain in a filter paper during filtration are termed as ___________________________
Boiling points of substance reflect the strength of __________________
The sub atomic particles of an atom are ____________________ and _____________________
Solar energy is example of _______________________resources
(b) Suggest the best method of separating the following mixture
Alcohol and water
Sodium chloride and water
Green solution from leaves
Sand from rice
Iron fillings and powder calcium carbonate
6. (a) Mrs. Janeth bought all necessary building materials as he wanted to build modern and expensive house for his mother, four months later he found out that almost all nails and Iron sheets have been rusted as she ignored leakage and small holes in the storage room, unfortunately he has no extra money to buy new nails and Iron sheets. As a chemistry student what will you advice Mrs. Janeth?
(b) Suppose you are in a bus traveling from Moshito Rombo for annual holiday, a bus driver went to the petrol station to fill fuel but he forgets to switch off the bus engine, this caused explosion and fire started. As a form four students:
(i) Will you be able to use fire extinguisher to fight against fire?
(ii) Which type of extinguisher will be suitable for you to use? Give reason of your choice
7. (a) Assign each of the properties to either luminous or non-luminous flame by putting a tick(?)on the respective column in the following table.
Property of Flame
Luminous Flame
Non- luminous Flame
Gives plenty of smoke and soot.
Blue in colour and almost invisible.
Yellow zone is larger than blue zone.
Formed when the air holes are completely closed.
Blue zone is larger than yellow zone.
Produces the hottest flame.
(b) Assume that you are doing an experiment in the laboratory at 07.30 pm and suddenly the lights go off. Give two reasons to justify the fact that you would consider luminous flame rather than non-luminous flame as an alternative source for lighting.
(c) Identify two properties of the flame produced by the Bunsen burner (air holes full opened) that can not be found in the flame produced by the spirit burner.
8. (a)Giving a reason, state whether rust will form or not in each of the situations (i) - (vi).
Iron bar is dipped into boiling water.
Painted iron bar is dipped into un-boiled water.
Iron bar is dipped in un-boiled water.
Oiled iron bar is left outside the room over nights.
Alluminium wire is dipped in un-boiled water.
A dry iron bar is wrapped with cotton wool.
(b)Briefly explain any four methods of preventing rusting.
9. (a)Why is petrol not recommended to be used as fuel in school laboratories? Briefly explain.
(b) Which three heat sources can be used to boil some water in the laboratory instead of the Bunsen burner?
(c) Arrange the following steps for lighting the Bunsen burner in a correct sequence using letter
Ato F.
Turn the collar to close the air hole completely.
Turn on the gas fully to ensure that plenty of gas is entering the burner.
Connect the Bunsen burner to the gas mains.
Adjust the gas tap until the supply of gas is enough for a time.
Light the gas at the top of the barrel with a lighted matchstick.
Close the air hole.
SECTION C (15 MARKS)
10.(a) Identify the five accidents which are common in the laboratory and in each explain possible causes and preventive measures to be taken.
(b). Briefly explain the five classes of fires based on the nature of the burning material and the extinguisher required. Give one example for each class.
MINISTRY OF EDUCATION, REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT
COMPETENCY BASED SECONDARY EXAMINATION SERIES
CHEMISTRY MID TERM EXAMINATION
FORM ONE- AUG/SEPT 2021
Time: 2:30Hours
Instructions.
This paper consists of section A, and B with a total of 10 questions
Answer all questions in spaces provided.
Section A carries 20 marks, section B 80 marks.
All answers should be written in the spaces provided.
All communication devices, calculators and any unauthorized material are not allowed in examination room.
Write your number on every page of your answer booklet.
SECTION A (20 Marks)
Answer All questions in this section.
For each of the items (i)-(x), choose the correct answer from the alternatives given.
(i) Air entering the Bunsen burner barrel can be controlled by
metal ring
air hole
metal jet
air ring
(ii) The appropriate extinguisher used to put off fire caused by cooking oil is:
Water extinguisher
Carbon extinguisher
Wet chemical extinguisher
Dry air extinguisher
(iii) A non-luminous flame is obtained if the hole is:
fully opened
partially opened
closed
half opened
(iv) Which of the following components can be separated by filtration method?
Sand and water
Kerosene and water
Ethanol and water
NaCl and water
(v) All domestic utensils made of iron undergo rusting when exposed to
Air and fire
Air and oil
Air and water
Water and oil
(vi) A change from gaseous state to solid state without passing through a liquid state is called:
Deposition
Sublimation
Condensation
Solidification
(vii) When a burning fuel produces blue colour it means there is:
A. adequate supply of oxygen with production of soot
B. inadequate supply of oxygen with production of more heat.
C. inadequate supply of oxygen with production of soot.
D. adequate supply of oxygen with production of more heat.
(viii) Why is water a universal solvent?
It is neither acidic nor basic than any other known liquid.
It dissolves more substances than any other known liquid.
It occurs naturally in all the three states of matter than any other liquid.
It dissolves both organic and inorganic solutes than any other liquid.
(ix) Which of the following gives the correct meaning of air?
Mixture of Nitrogen, Oxygen and dust particles.
Mixture of Nitrogen, Oxygen and Carbon dioxide.
Mixture of Nitrogen, Oxygen and Water vapour
Homogenous mixture of gases.
(x) Which of the following is the best apparatus for measuring accurately the volume of a given solution?
Measuring cylinder
Burette
Beaker
Conical flask
2. (a)Match each item in List A with a correct response in List B by writing the letter of the correct response below the corresponding item number in the table provided.
LIST A
LIST B
Miscible liquid
Gas used in balloons
A liquid metallic element
Burning back
Used in combustion
Water and kerosine
Water and alcohol
Excess gas
Flame rise in burrel
Nitrogen
Neon
Argon
Oxygen
Helium
Mercury
Bromine.
(b) Answer the given questions by writing the correct answer in the blank spaces provided.
The smallest particle of matter……………….
Used to prepare a solution with known concentration…………..
Preventing rusting by covering with zinc………………………
The most abundance gas in air…………………..
Turns lime water milky………………
SECTION B (80 Marks)
Answer all questions in this section.
3. (a) Mariam was preparing food for her family using hot oil in a frying pan. Accidentally the pan tripped over and a huge fire spread over her kitchen floor.
(i)Mention two extinguishers which would be appropriate for putting out the fire.
(ii)Which fire extinguisher would be dangerous to use when trying to put out the fire in (a) above? Give reason. (b) Mention three conditions for a fire to start.
(c) (i) What is combustion?
(ii) Give three areas where combustion is applied.
4. (a) List down four careers that are a result of studying Chemistry.
The following are possible causes of accidents which can occur in the Chemistry laboratory. State how you can avoid them.
(i)Poisonous chemicals left in an unlocked cupboard .........
(ii)A student picking up a bottle containing concentrated H2S04 acid by the neck .........
(iii)Concentrated acids stored in the upper most shelf of cupboard
5.(a) Differentiate between:
(i)an atom and an element
(ii)Combustion and rusting
(iii)a solute and a solvent
(iv)a compound and a mixture
(b)Give two applications of chemistry in everyday life
(c)Why most laboratory apparati are made of glass?
6. Identify the five accidents which are common in the laboratory and in each explain possible causes and preventive measures to be taken.
7. (a) Why candles are not suitable for heating in the laboratory? Give two reasons.
(b) Differentiate luminous from non-luminous flame by giving five points.
8. (a) State one use of each of the items (i) – (x) in administering First Aid.
S/N
Item
Use
(i)
Soap
(ii)
Bandage
(iii)
Sterile gauze
(iv)
Iodine tincture
(v)
Petroleum jelly
(b) Effective use of the four senses of observation is important before a chemist can make conclusion. With four points, show how the senses are used as tools of observation during experimentation by giving one example for each.
(i) ………… ………… ……………
(ii) ………… …………… ………….
(iii) ………… ……………… …… ….
(iv) ………… …………… ……………
9. Briefly explain the five classes of fires based on the nature of the burning material and the extinguisher required. Give one example for each class.
10. Define the following terms:
(i) Brownian motion
(ii) Compound
(b) Identify whether the following is a physical or chemical change:
(i) Cutting aluminium foil into pieces
(ii) Lighting a match .
(c) How can you separate the following mixtures? Briefly explain.
MINISTRY OF REGIONAL GOVERNMENT AND LOCAL GOVERNMENT
AUGUST-SEPTEMBEREXAMINATION SERIES
CHEMISTRYFORM-1
2020
2:30 HOURS
INSTRUCTIONS.
This paper consists of sections A and B with a total of ten (10) questions.
Answer all questions in spaces provided.
All writing must be in blue or black ink except drawing which must be in pencil.
Calculators, cellular phones and any unauthorized materials are not allowed in the examination room.
Write your Examination Number at the top right corner of every page.
The following atomic masses may be used; H =1, N =14, O = 16, S = 32, Ca = 40
SECTION A (20 Marks)
Answer all questions in this section.
1.For each of the items (i) –(x), choose the correct answer from the among the given alternatives and write its letter in the box provide.
(i) What is the best way of keeping a clean test tube after use?
Keeping it in water
Keeping it on a test tube holder
Keeping it in a basin for test tubes
Keeping it on a test tube rack.
(ii) Which one of the following does not involve the processes of urban water treatment and purification?
Sedimentation
Distillation
Filtration
Chlorination.
(iii) Why hydrogen gas is not a constituent of air?
Because of being water soluble
Because of being denser than air
Because of being very light
Because of being highly flammable.
(iv) Which is the suitable alternative heat source to be used in absence of Bunsen Burner?
Torch and spirit burner
Torch and kerosene stove
Kerosene stove and spirit burner
Firewood and torch.
(v) What happens when substance A reacts with substance B to form a new substance C?
Substance A and B are said to have formed a solution
Substance A and B are said to have undergone a physical change.
Substance A and B are said to have undergone a chemical change.
Substance A and B are said to have undergone a dissolution.
(vi) Which components make fire triangle?
Oxygen, fuel and heat
Oxygen, nitrogen and heat
Oxygen, fuel and carbon dioxide
Oxygen, heat and hydrogen.
(vii) Which state is involved when drying wet clothes?
Liquid to solid
Solid to gas
Gas to liquid
Liquid to gas.
(viii) Why Non – luminous flame is the most applicable flame for heating purposes?
It is very nosy
It has no soot.
It is very hot
It has air holes open
(ix) Chemistry is a branch of Science which deals with:
matter in relation to energy.
matter in relation to decomposition.
matter composition and its decomposition.
properties of conservation of matter.
(x) The process of removing solid contaminants from water is known as:
water decantation.
water solidification.
water purification.
water sedimentation.
2. (a) Match each item in List A with a correct response in List B by writing the letter of the correct response below the corresponding item number in the table provided.
List A
List B
(i)A solvent which dissolves most substances to form solution.
(ii)A substance that has no definite shape or size.
(iii)A substance that has a fixed shape and volume
(iv)A substance whose components can be separated by physical means
(v)Homogeneous mixture of two or more substances.
Solid
Solution
Water
Sugar
Milk
Gas
Liquid
Air
(b) Fill in the blank spaces by using the appropriate terms
(i)Solid particles formed after filtration......................
(ii)Serum is separated from blood samples by employing a technique called………………..
(iii)Boiling points of substances reflect the strength of……………….
(iv)Grinding chalk into a powder involves changing the state of …………………….
(v) The liquid formed after filtration..........................
SECTION B (80 Marks)
Answer all questions in this section.
3. (a) State one use of each of the items (i) – (x) in administering First Aid.
S/N
Item
Use
(i)
Soap
(ii)
Bandage
(iii)
Sterile gauze
(iv)
Iodine tincture
(v)
Petroleum jelly
(b) Give one function of each of the following apparatus in the chemistry laboratory.
(i) Spatula…………… …………… ……………….
(ii) Gas jar…………… ……………. …… ……….
(iii) Lie – big condenser …………… …… …………
(iv) Motor and pestle…… …………… ……………
(v) Wire gauze… ………… ………… …………….
4. (a) Differentiate hypothesis from analysis.
(b) Effective use of the four senses of observation is important before a chemist can make conclusion. With four points, show how the senses are used as tools of observation during experimentation by giving one example for each.
(i)………… ………… ……………
(ii)………… …………… ………….
(iii)………… ……………… …… ….
(iv)………… …………… ……………
5. What precautions will you take in handling chemicals having the warning signs shown in the table? Give two precautions in each sign.
S/N
Sign
Relevant Precaution
a)
EXPLOSIVE
(i)………… ……… …………… ….
(ii)………… ………… …………….
b)
FLAMMABLE
(i)…………… …………… ….
(ii)………… ………… …… ….
c)
TOXIC
(i)…… …………… …………….
(ii)……… …………… ………….
d)
CORROSSIVE
(i)…………… ……………… …….
(ii)…………… ………… ………….
e)
OXIDANT
(i)…………… ……… …………….
(ii)…………… …………… ……….
6. Briefly explain the five classes of fires based on the nature of the burning material and the extinguisher required. Give one example for each class.
7. Explain three factors which affect the problem being investigated (b) Explain two areas where scientific procedure is applied.