Explain why the following combination of reagents is unsuitable for the laboratory preparation of hydrogen.

Explain why the following combination of reagents is unsuitable for the laboratory
preparation of hydrogen.
(i) Zinc + dilute nitric acid.
(ii) Lead + dilute hydrochloric acid.
(iii) Potassium + dilute sulphuric acid.

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(i) Zn(s) + HNO₃(aq) - HNO₃ is oxidizing agent, H₂O immediately.
(ii) Pb(s) + HCl(aq) - PbCl₂ formed is insoluble, prevents further reaction.
(iii) K(s) + H₂SO₄(aq) - Reaction of K(s) with H₂SO₄(aq) is explosive

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sharon kalunda answered the question on May 17, 2019 at 11:21

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