1st Year Chemistry 4th Quarter Book Paper

Q1. Multiple choice questions (Attempt all · 12 × 1 = 12)

1. The mobile source of air pollution is:

   1. Cement factory

   2. Power plant

   3. Airplane

   4. Oil refinery

2. Ion gives a yellow precipitate with ammonium molybdate and nitric acid:

   1. Sulfate

   2. Carbonate

   3. Phosphate

   4. Chloride

3. AgNO₃ forms a precipitate with a halide ion due to formation of:

   1. Ionic bonds

   2. Complex compounds

   3. Silver halide salts

   4. Covalent halide radicals

4. For effective separation using simple distillation, the minimum required difference in boiling points between the components should be approximately:

   1. 5°C

   2. 10°C

   3. 15°C

   4. 25°C or more

5. Which atmospheric layer would a commercial airplane typically fly in to avoid weather turbulence?

   1. Troposphere

   2. Stratosphere

   3. Mesosphere

   4. Thermospher

6. ......must be neutralized before disposal.

   1. Alcohols

   2. Salts

   3. Acids and bases

   4. Water

7. Halide ion that reacts with concentrated H₂SO₄ to release HCl gas?

   1. Br^-

   2. Cl^-

   3. l^-

   4. F^-

8. Which of the following techniques is an example of partition chromatography?

   1. Column chromatography

   2. Thin layer chromatography

   3. Paper chromatography

   4. Size exclusion chromatography

9. CFCs are harmful to the environment because of:

   1. They cause acid rain

   2. They deplete the ozone layer in the stratosphere

   3. They increase air temperature directly

   4. They cause water pollution

10. A fire hazard in the lab may occur due to:

    1. Water spills

    2. Metal wires

    3. Ether vapors

    4. Plastic beakers

11. Which silver halide dissolves only in concentrated ammonia?

    1. AgCl

    2. AgBr

    3. Agl

    4. AgF

12. The main function of a filter medium during filtration is to:

    1. Absorb the solid

    2. Mix the components of the mixture

    3. Trap the solid while allowing the liquid to pass through

    4. Dry the filtrate