In order to prepare hydrogen gas in the laboratory a student set-up the apparatus shown in the diagram below. Study it and answer the questions...

In order to prepare hydrogen gas in the laboratory a student set-up the apparatus shown in the diagram below. Study it and answer the questions that follow.


(a) Suggest why the student did not collect hydrogen gas.
(b) In a separate experiment the student reacted iron and hydrochloric acid to prepare hydrogen gas.
(i) Write an ionic equation for the reaction.
(ii) The hydrogen gas produced was found to have a foul smell. Suggest an explanation for this.

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a) conc. HNO₃ is a strong oxidizing agent. It oxidizes and thickens the thin coating of aluminium oxide thus leading to no reaction between metal and acid.

b) i

ii.Sulphide impurities in the iron react with the acid to form hydrogen sulphide gas which has foul smell.

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maurice.mutuku answered the question on September 3, 2019 at 07:27

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