Candidate's Examination Number . . . . . . . . . . . . . .

THE UNITED REPUBLIC OF TANZANIA, NATIONAL EXAMINATIONS COUNCIL

FORM TWO SECONDARY EDUCATION EXAMINATION, 2010

0032 CHEMISTRY

Time: 2½ HOURS

INSTRUCTIONS

1. This paper consists of sections A, B and C.
2. Answer ALL questions.
3. Write your examination number at the top right corner of every page.
4. ALL writing must be in black or blue ink EXCEPT diagrams which must be in pencil.
5. Cellphones and calculators are not allowed in the examination room.
6. The following atomic masses may be used: H = 1, O = 16, C = 12, Na = 23, S = 32, Ca = 40.

SECTION A (10 MARKS)

1. Questions (i) - (x) are multiple choice items. Select the best answer in each case and write its letter (A, B, C, or D).

(i) In scientific study, the tentative explanation for the observed chemical phenomenon can be proved by:

1. Data analysis
2. Experimentation
3. Hypothesis
4. Observation

(ii) A certain liquid dissolves copper (Il) sulphate to form a blue solution. This liquid is likely to be:

1. Hydrochloric acid
2. Liquid oxygen
3. Nitric acid
4. Water

(iii) When a chemist studies a substance he/she is interested in its:

1. Force of attraction
2. Properties
3. Shape
4. Smell

(iv) The boiling point of pure water at sea level is 100⁰C and that of ethanol is 78⁰C. The mixture of ethanol and water can be separated by:

1. Filtration process
2. Fractional distillation process
3. Layer separation process
4. Sublimation process

(v) The boiling point of pure water at sea level is 100⁰C and that of ethanol is 78⁰C. The mixture of ethanol and water can be separated by:

1. Filtration process
2. Fractional distillation process
3. Layer separation process
4. Sublimation process

(vi) Which group among the following elements are metals?

1. Calcium, magnesium and sodium
2. Calcium, hydrogen and nitrogen
3. Calcium, carbon and magnesium
4. Oxygen, potassium and sodium

(vii) An electrovalent bond is formed by:

1. Arrangement of electrons
2. Sharing of electrons
3. Transfer of electrons
4. Vibrations of electrons

(viii) Petrol is an example of:

1. corrosive substance
2. flammable substance
3. irritating substance
4. toxic substance

(ix) The electronic configuration of silicon is:

1. 2:7:3
2. 2:8:2
3. 2:8:3
4. 2:8:4

(x) The most abundant element on the earth is:

1. carbon
2. iron
3. nitrogen
4. oxygen