Ch.18 - ElectrochemistryWorksheetSee all chapters
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Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Solution: A 1L solution containing 0.110 M NiCl 2(aq) and 0.200 M CuBr2(aq) is subjected to electrolysis.How much time would it take to selectively plate out one of the cations at a current of 5.0 A?

Solution: A 1L solution containing 0.110 M NiCl 2(aq) and 0.200 M CuBr2(aq) is subjected to electrolysis.How much time would it take to selectively plate out one of the cations at a current of 5.0 A?

Problem

A 1L solution containing 0.110 M NiCl 2(aq) and 0.200 M CuBr2(aq) is subjected to electrolysis.

How much time would it take to selectively plate out one of the cations at a current of 5.0 A?


Solution

We’re being asked to calculate for the time it would take to selectively plate out one of the cations in the given solution.

The solution is made up of 0.110 M NiCl2(aq) and 0.200 M CuBr2(aq) and subjected to electrolysis. Both will break up in the solution:

NiCl2(aq) → Ni2+(aq) + 2 Cl-(aq)

CuBr2(aq) → Cu2+(aq)+ 2 Br-(aq) 


Let’s first determine which cation (positively charged ion) will be plated out from the solution first. The one with the higher reduction potential will be plated out first.

*the standard reduction potential table (E°cell values) can be found in books or on the internet

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