Question

by which process bubbles of a gas may be formed​

Answer 1

Bubbles of a gas are generally formed in displacement or decomposition reactions

In displacement, an element can replace the gaseous substance

eg. Zn + 2HCl (☞ﾟヮﾟ)☞ ZnCl2 + H2

Here H2 gas is evolved

Similarly

2CO2 (☞ﾟヮﾟ)☞ 2CO + O2

Here Oxygen gas is evolved

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Answer 2

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