THE UNITED REPUBLIC OF TANZANIA NATIONAL EXAMINATIONS COUNCIL OF TANZANIA

FORM TWO NATIONAL ASSESSMENT

032 CHEMISTRY

Time: 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 the spaces provided
3. All writing must be in black or blue ink except diagrams which must be in pencil
4. 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.

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)Identify the set of chemistry products which are used for domestic cleanliness

1. Tooth paste, oils, detergents and deodorants
2. Soap, deodorants, tooth paste and fuel
3. Detergents, soap, tooth paste and deodorants
4. Drugs, tooth paste, soap and oils

(ii) 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

(iii) Your friends were arguing about the scientific procedure that follows after data interpretation. Which stage will you suggest to your friends?

1. Observation
2. Hypothesis
3. Conclusion
4. Experimentation

(iv) The teacher was demonstrating an experiment by dissolving sodium chloride in water until the solute was not dissolving any more. What type of solution formed at the end of the experiment?

1. Saturated
2. Unsaturated
3. Super saturated
4. Suspension

(v) A large percent of air is composed of

1. Nitrogen
2. Noble gases
3. Carbon dioxide
4. Oxygen

(vi) John and Asha were debating about the process that are involved during simple distillation. What processes will you recommend to them?

1. Filtration and decantation
2. Condensation and decantation
3. Evaporation and filtration
4. Evaporation and condensation

(vii) Form Two student discovered that it is impossible to light fire in a vacuum due to absence of a certain gas. What comment can you give to the student?

1. Nitrogen is missing
2. Oxygen is missing
3. Carbon dioxide is missing
4. Hydrogen is missing

(viii) Atomic structures of all elements consist of electrons, protons and neutrons except that of

1. Hyadrogen
2. Nitrogen
3. Oxygen
4. Carbon

(ix) When referring to the modern Periodic Table, the transition elements are found between:

1. Group I and II
2. Group I and III
3. Group II and III
4. Group III and IV

(x) Given that, element “M” with electronic configuration of 2:8:3 combines with element “G” with electronic configuration of 2:6 to form a compound; What is the chemical formula of the compound formed.

1. G₃M₂
2. M₂G₃
3. G₂M₃
4. M₃G₂