Science — AI-generated practice question

When zinc granules react with dilute sulphuric acid, hydrogen gas (H₂) is evolved.

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

Test: A burning candle or matchstick is brought near the mouth of the test tube. Hydrogen gas burns with a pop sound, confirming its presence.

Source: Chapter 1, Section 1.1.2; Chapter 2

• The first mark is for correctly naming hydrogen gas (and ideally writing the equation).
• The second mark is for the test — examiners specifically want: burning splint/candle + pop sound. Both details are needed for full credit.
• Do not confuse the test for H₂ (pop sound) with CO₂ (turns lime water milky) — a common mistake.