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Redox reactions paper 1 question, help!

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How do you go forward with this question?

When the same quantity of electricity was passed through a dilute solution of sodium hydroxide and through a molten soluton of lead bromide, 0.100 mol of lead was produced. What amount (in mol) of hydrogen gas was evolved?

A. 0.014

B. 0.050

C. 0.100

D. 0.200

Don't we need the Data Booklet for this one?

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4 hours ago, anishaaas said:

How do you go forward with this question?

When the same quantity of electricity was passed through a dilute solution of sodium hydroxide and through a molten soluton of lead bromide, 0.100 mol of lead was produced. What amount (in mol) of hydrogen gas was evolved? A. 0.014 B. 0.050 C. 0.100 D. 0.200 Don't we need the Data Booklet for this one?

Well assume the electrolysis reaction proceeds. There is either lead (II) bromide and lead (IV) bromide
In dilute sodium hydroxide
Cathode: 2H+ + 2e- --> H(Anode makes oxygen gas)

If lead (II) bromide
Cathode: Pb2+ + 2e- --> Pb (Anode makes bromine gas)
Lead : hydrogen ratio is 1:1 ====> 0.100 mol of hydrogen gas. Choice C.

If lead (IV) bromide
Cathode: Pb4+ + 4e- --> Pb
Now double the sodium hydroxide equation to match number of electrons
4H+ + 4e- --> 2H
Lead : hydrogen ratio is 1: 2. ==> 0.200 mol of hydrogen gas. Choice D
Note that predicting relative products quantity is in 19.1 of the chemistry guide. Molten solutions are covered in 9.2; dilute aqueous solutions are in 19.1.

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