The following are the uses of chromatography except:

1. to analyse blood in crime scenes.
2. to detect different fibres.
3. to detect water pollution.
4. to bleach dye/colour.
5. to test purity of organic substances.

  What is the proper set of apparatus would you use to grind granules of a solid substance into fine powder in the laboratory?

1. Pestle and filter funnel   
2. Separating funnel and mortar
3. Pestle and filter paper                  
4. Pestle and mortar
5. Thistle funnel and mortar

THE UNITED REPUBLIC OF TANZANIA NATIONAL EXAMINATIONS COUNCIL

CERTIFICATE OF SECONDARY EDUCATION EXAMINATION 

032/1  CHEMISTRY 1

 (For Both School and Private Candidates)

Time: 3 Hours  Thursday, 11^th October 2012 p.m.

 Instructions

1.  This paper consists of sections A, B and C.
2.  Answer all questions in this paper.
3.  Calculators and cellular phones are not allowed in the examination room.
4.  Write your Examination Number on every page of your answer booklet(s).
5.  The following constants may be used.

 Atomic masses:

 H = 1, C = 12, O = 16, N = 14, Na = 23, Mg = 24, Al = 26, S = 32, Cl = 35.5, Ca = 40, Mn = 55, Fe = 56, Cu = 64.

 Avogadro’s number = 6.02 x 10²³.

 GMV at s.t.p. = 22.4 dm³.

 1 Faraday = 96,500 coulombs.

 Standard pressure = 760 mm Hg.

 Standard temperature = 273 K.

 1 litre = 1 dm³ = 1000 cm³.

SECTION A (20 Marks)

Answer all questions in this section.

1. For each of the items (i) – (x), choose the correct answer from the given alternatives and write its letter beside the item number in the answer booklet provided.

(i)  Which one of the following sets of laboratory apparatus are used for measure volume?

1. Crucible, U-tube and volumetric flask
2. Test tubes, beakers and glass jar
3. Thistle funnel, separating funnel and beaker
4. Burette, pipette and measuring cylinder
5. Conical flask, test tube and measuring cylinder.

(v) A solvent can be obtained from a solution by

1.  evaporation followed by decantation
2.  filtration and condensation
3.  evaporation and filtration
4.  evaporation and condensation
5.  crystallization followed by sublimation.

THE UNITED REPUBLIC OF TANZANIA NATIONAL EXAMINATIONS COUNCIL OF TANZANIA

FORM TWO NATIONAL ASSESSMENT

032   CHEMISTRY

Duration: 2:30 Hours

INSTRUCTIONS. 

1. This paper consists of sections A and B with a total of ten (10) questions.
2. Answer all questions in spaces provided.
3. All writing must be in blue or black ink except drawing which must be in pencil.
4. Calculators, cellular phones and any unauthorized materials are not allowed in the examination room.
5. Write your Examination Number at the top right corner of every page.
6. 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?

1. Keeping it in water
2. Keeping it on a test tube holder
3. Keeping it in a basin for test tubes
4. Keeping it on a test tube rack.

Fainting is a sudden loss of:

1. confidence. 
2. weight of the body. 
3. water in the body. 
4. consciousness.

Fainting is a sudden loss of:

1. confidence. 
2. weight of the body. 
3.  water in the body. 
4.  consciousness.

 Which among the following are the two processes involved during distillation?

1. Evaporation and sublimation 
2. Evaporation and crystallization
3. Evaporation and condensation 
4. Evaporation and decantation

Which of the following is the best apparatus for measuring accurately a fixed volume of a given solution?

 A. Measuring cylinder          B. Beaker

   C. Pipette                            D. Burette

Which of the following is not a component of the First Aid Kit?

1. Goggles 
2.  A pair of scissors
3.  Dropper 
4.  Gloves
5.  Razor blade

   Which of the following group of substances represents flammable liquids?

1. Petrol, pesticides, hydrogen;
2. Petrol, sulphuric acid, methylated spirit;
3. Methylated spirit, petrol, kerosene;
4. Kerosene, diesel, hot water. 

Which of the following is not a component of the First Aid Kit?

1. Goggles
2. A pair of scissors
3. Knife
4. Gloves
5. Razor blade

(iv)  Fractional distillation process of a mixture of water and ethanol is possible because

1. water and ethanol have the same boiling point
2. water has lower boiling point than ethanol
3. ethanol has lower boiling point than water
4. water and ethanol form partially immiscible liquid solution
5. water and ethanol are immiscible liquids.

Which of the following is the best apparatus for measuring accurately the volume of a given solution?

1. Measuring cylinder
2. Burette
3. Beaker
4. Conical flask

The apparatus used for grinding granular chemicals in the laboratory include:

1. Crucible and watch glass
2. Mortar and pestle
3. Pestle and pair of tongs 
4. Spatula and basin

 Flammable chemicals are those which:

1. Burn skin
2. Catch fire easily
3. Explode
4. Extinguish fire

Which of the following apparatuses is suitable for measuring volumes of smaller quantities of liquids?

A.Beaker    

B. Burette

C. Conical flask 

D. Measuring cylinder

Petrol is an example of:

           A.corrosive substance         

          B. flammable substance 

          C. irritating substance   

          D. toxic substance

 Which method could be used to separate the products in the following equation?

1.  Chromatography
2. Crystallisation 
3. Distillation 
4. Filtration 
5. Condensation.

The following is a set of apparatuses which are used for heating:

A.crucible, test tube, evaporating dish

B.evaporating dish, tongs, crucible

C.test tube, evaporating dish, tongs

D.tongs, crucible, test tube

   Which of the following warning signs is likely to appear on the bottle containing concentrated Nitric Acid in the laboratory? 

1. Corrosive
2. Explosive
3. Flammable 
4. Irritant

 Which statement is the most correct about chemistry laboratory?

1. Is a special room designed for conducting chemical tests.
2. Is a special room designed for science practicals.
3. Is a special room designed for keeping apparatuses. 
4. Is a special room where data analysis is carried out.
5. Is a special room where students learn chemistry.

During practical work a measuring cylinder was used to prepare oxygen by decomposing hydrogen peroxide. What is the function of the cylinder in this experiment?

1. To measure volume
2. To measure weight
3. To measure width
4. To measure volume length

Water can be obtained from a solution of common salt by

1. evaporation
2. simple distillation
3. filtration
4. condensation
5. fractional distillation.

(x)  _____ is the general term used to explain a mixture of different metals.

1. Alloy
2. Allotrope
3. Amphoteric
4. Amorphous 
5. Isotope.

8.   Explain each of the following terms:

(i)Burn

(ii)  Bruises

(iii)Fainting ..............................................

8.(a) Calculate the oxidation number of the underlined elements:

(ii)

(b)What is the use of each of the following apparatus? (i) Thistle funnel    (ii) Pipette .........

 (iii) Wire gauze .........          (iv) Burette .........

8.

(b)      What is the use of each of the following apparatuses?

(i)Tongs .      (ii) Spatula.........

(iii) Pipette.........     (iv) Crucible .........

Give the use of each of the following components which are found in the First Aid kit:

(i) Plaster .........

(ii) A pair of scissors

(iii) Cotton wool ......... 

(iv) Gloves ......... 

 Match the uses of First Aid Kit items in List A with the respective items in List B by writing the letter of the correct response besides the item number in the answer booklet provided.

(a) List down four careers that are a result of studying Chemistry.

(b)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

Give four laboratory apparatuses that are made up of porcelain/ceramic material.

Outline three steps of administering First Aid to a person having a bruise on his leg resulting from a fist /hand blow.

(a) (i) Name two reagents normally used for preparation of hydrogen in the laboratory.

(ii) Write a word equation for the reaction in (i) above.

(b)      (i) Why is hydrogen gas used for filling balloons? (ii) Describe chemical test for hydrogen gas.

(c)      Explain safety measures that should be taken when handling chemicals with the following warnings: (i) Flammable

(ii)Corrosive

(iii)Irritant or Harmful

(iv)Toxic