Activity 2.3
CAUTION: This activity needs the teacher’s assistance.
CAUTION: This activity needs the teacher’s assistance.
- Set the apparatus as shown in Fig. 2.1.
- Take about 5 mL of dilute sulphuric acid in a test tube and add a few pieces of zinc granules to it.
- What do you observe on the surface of zinc granules?
✅ Answer: Hydrogen gas bubbles are formed on the surface of zinc granules.
- Pass the gas being evolved through the soap solution.
- Why are bubbles formed in the soap solution?
✅ Answer: Soap bubbles filled with hydrogen are formed.
- Take a burning candle near a gas-filled bubble.
- What do you observe?
✅ Answer: Hydrogen burns with a pop sound.
- Repeat this Activity with some more acids like HCl, HNO3 and CH3COOH.
- Are the observations in all the cases the same or different?
✅ Answer: Bubbles come out vigorously with strong acids. Zinc also reacts with weak acids like acetic acid, but gas is formed slowly.
