THE UNITED REPUBLIC OF TANZANIA, NATIONAL EXAMINATIONS COUNCIL

FORM TWO SECONDARY EDUCATION EXAMINATION

0032 CHEMISTRY

Time: 2:30 Hours Year 2014

Instructions

1. This paper consists of sections A, B and C.
2. Answer all questions in the spaces provided.
3. All writing must be in black or blue ink except diagrams which must be in pencil.
4. All communication devices and calculators 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, O = 16, C = 12, N = 14, Na = 23, P = 31, S = 32, K = 39, Ca = 40.

SECTION A (10 Marks)

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

(i) An isotope of carbon has an atomic number 6 and a mass number of 14, this means that it has

1. 6 protons, 8 neutrons, 6 electrons
2. 8 protons, 6 neutrons, 8 electrons
3. 6 protons, 14 neutrons, 6 electrons
4. 14 protons, 6 neutrons, 14 electrons

(ii) Which of the following gives the correct meaning of air?

1. Mixture of Nitrogen, Oxygen and dust particles.
2. Mixture of Nitrogen, Oxygen and Carbon dioxide.
3. C. Mixture of Nitrogen, Oxygen and Water vapour
4. Homogenous mixture of gases.

(iii) Why is water a universal solvent?

1. It is neither acidic nor basic than any other known liquid.
2. It dissolves more substances than any other known liquid.
3. It occurs naturally in all the three states of matter than any other liquid.
4. It dissolves both organic and inorganic solutes than any other liquid.

(iv) How many numbers of shells are there in Magnesium atom?

1. 1
2. 2
3. 3
4. 4

(v) Technicians prefer to use blue flame in welding because: