Science (086) — AI-generated practice question

The gas evolved is hydrogen (H₂).

$$\text{Zn}(s) + \text{H}_2\text{SO}_4(aq) \rightarrow \text{ZnSO}_4(aq) + \text{H}_2(g)$$

Confirmation: When a burning candle/matchstick is brought near the mouth of the test tube collecting the gas, it burns with a pop sound, confirming it is hydrogen gas.

Source: Chapter 1, Section 1.1.2 (Balanced Chemical Equations)

---

• 1 mark: Correctly naming the gas as hydrogen and writing the equation.
• 1 mark: Describing the test — "pop sound" with a burning splint/candle is the standard textbook test for hydrogen. Examiners expect both the method and the observation (pop sound) for full credit. Simply writing "it burns" is insufficient.