9th class Chemistry, Chapter 13: Laboratory and Practical Skills MCQs

1. Safety in the chemistry laboratory is:

1. (A) the responsibility of the students only
2. (B) the responsibility of the professor only
3. (C) the responsibility of the lab. incharge only
4. (D) a shared responsibility ✓

2. Accidents often result from:

1. (A) making mistakes
2. (B) failure to use common sense
3. (C) failure to follow instructions
4. (D) all of the above ✓

3. The label "Warning" on a chemical bottle signifies:

1. (A) that the chemical can cause less serious injury
2. (B) that the chemical can cause serious injury
3. (C) that user should be careful when using chemical ✓
4. (D) that user should open it only in the presence of a teacher

4. The label "Corrosive" on a chemical bottle indicates:

1. (A) that the material is an oxidizing agent
2. (B) that the material can degrade rapidly upon exposure
3. (C) that its contact destroys living tissue ✓
4. (D) that the chemical can explode

5. Example of highly toxic chemical:

1. (A) Ethanol
2. (B) Acetic acid
3. (C) Potassium cyanide ✓
4. (D) Potassium permanganate

6. Example of self-reactive chemical:

1. (A) Potassium
2. (B) Phenol
3. (C) Picric acid ✓
4. (D) n-Hexane

7. When diluting an acid with water:

1. (A) do it quickly
2. (B) do not stir the container
3. (C) always add acid to water ✓
4. (D) always add water to acid

8. What should you do in case of a fire drill in the lab.?

1. (A) run to safety shower
2. (B) climb into the fume cupboard
3. (C) close gas valves and turn off all equipments ✓
4. (D) carry chemicals out of the lab.

9. To smell a gas in the laboratory, you should:

1. (A) Smell it directly from the tube
2. (B) Taste it
3. (C) Heat it and inhale
4. (D) Waft the fumes towards your nose ✓

10. Acids and bases are disposed off by:

1. (A) Neutralizing first, then sewer disposal ✓
2. (B) Pouring directly into drains
3. (C) Throwing into the trash
4. (D) Storing in the refrigerator

11. Chemicals that cause a sudden release of pressure, gas and heat on sudden shock are called:

1. (A) Asphyxiants
2. (B) Explosive chemicals ✓
3. (C) Corrosive chemicals
4. (D) Toxic chemicals

12. Flammable chemicals have a flashpoint around:

1. (A) 0 K
2. (B) Room temperature ✓
3. (C) 100 °C
4. (D) 500 °C

13. Which of the following is a flammable compound?

1. (A) Acetone ✓
2. (B) Sodium chloride
3. (C) Water
4. (D) Calcium carbonate

14. While working with corrosive chemicals one should wear:

1. (A) No eye protection
2. (B) Splash goggles and a face shield ✓
3. (C) Ordinary sunglasses
4. (D) Contact lenses

15. Corrosive chemicals must be used in a:

1. (A) Fume cupboard ✓
2. (B) Refrigerator
3. (C) Open field
4. (D) Closed cupboard

16. Which of the following is a toxic chemical?

1. (A) Glucose
2. (B) Distilled water
3. (C) Mercury ✓
4. (D) Sodium chloride

17. Toxic chemicals should be kept in:

1. (A) Food containers
2. (B) Open beakers
3. (C) Unlabelled bottles
4. (D) Their original container ✓

18. Which of the following is a reactive chemical?

1. (A) Glass
2. (B) Water
3. (C) Calcium hydride ✓
4. (D) Sand

19. A high dose of radiation can cause:

1. (A) Faster growth
2. (B) No effect
3. (C) Radiation burns and hair loss ✓
4. (D) Better eyesight

20. Exposure to radiation is monitored using:

1. (A) Barometers
2. (B) Badges ✓
3. (C) Thermometers
4. (D) Litmus paper