Chemistry
Which metal does not react with HCl to form a colourless, odourless gas which burns with a pop sound?
- Ca
- Mg
- Cu
- Zn
Answer
Cu
Reason — Hydrochloric acid reacts with metals like Ca, Mg and Zn, which are above hydrogen in the activity series forming metallic chlorides and evolving hydrogen, it is a colourless, odourless gas which burns with a pop sound.
Whereas, Cu is less reactive than hydrogen and present below hydrogen in the activity series, thus it cannot displace hydrogen from HCl.
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