NCERT In-text 2.1 — Q2 - Acids, Bases and Salts
Question: Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence of this gas?
Answer: Hydrogen gas. Example: Zn + H2SO4 — ZnSO4 + H2. Test: burning splinter produces a pop sound.
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