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Subject Test Chemistry

Question 2 of 13

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The set of lettered choices below refers to multiple questions. Select the one lettered choice that best fits each statement or answers each question. A choice may be used once, more than once, or not at all in each set.

Electrolysis of water to form hydrogen and oxygen gases

Select an Answer

Precipitation

Correct Answer: 
No

Oxidation-reduction

Correct Answer: 
Yes

Distillation

Correct Answer: 
No

Hydration

Correct Answer: 
No

Condensation

Correct Answer: 
No

The chemical equation for this reaction is
2 text H end text subscript 2 end subscript text O end text left parenthesis l right parenthesis invisible times rightwards arrow 2 text H end text subscript 2 end subscript left parenthesis g right parenthesis invisible times plus text O end text subscript 2 end subscript left parenthesis g right parenthesis.

Note that the oxidation number of hydrogen changes from plus 1 to 0, and the oxidation number of oxygen changes from negative 2 to 0. Hydrogen gains electrons and oxygen loses electrons. This is an oxidation-reduction reaction.

Question Difficulty: 
medium