Answer the following questions.

1. The hardness of the bone tissue is due to the phosphates and carbonates of which of the following pairs of elements?

a) calcium and sodium
b) magnesium and sodium
c) calcium and potassium
d) calcium and magnesium

2. Which solvent is used for dry-cleaning clothes?

a) acetone
b) alcohol
c) carbon tetrachloride
d) chloroform

3. Which one of the following compounds is used as a sedative?

a) potassium bromide
b) calcium chloride
c) ethyl alcohol
d) phosphorous trichloride

4. Which one of the following is an anti-knocking agent added to petrol?

a) ethyl alcohol
b) white petrol
c) tetra ethyl lead
d) butane

5. The chemical composition of marble is mostly

a) calcium carbonate
b) potassium carbonate
c) sodium carbonate
d) strontium carbonate

6. Which of the following sulphur compound is used as a bleaching agent in textile industry?

a) carbon disulphide
b) sulphur dioxide
c) sulphuric acid
d) hydrogen sulphide

7. Which of the following compounds are responsible for acid rain?

a) nitrogen dioxide and silicon dioxide
b) nitrogen dioxide and sulphur dioxide
c) nitrogen dioxide and carbon monoxide
d) silicon dioxide and carbon monoxide

8. Which radioactive pollutant occurs in building materials?

a) plutonium
b) thorium
c) radon
d) radium

9. Which quality of water makes it a good solvent of ionic salts?

a) it has a high melting point
b) it has a high dipole moment
c) it has a high specific heat
d) it has no colour

10. Monazite is an ore of

a) zirconium
b) thorium
c) titanium
d) iron

Answers

1. calcium and sodium
2. alcohol
3. potassium bromide
4. tetra ethyl lead
5. calcium carbonate
6. sulphur dioxide
7. nitrogen dioxide and sulphur dioxide
8. thorium
9. it has high dipole moment
10. thorium