When the zinc plate in one of Edison's coulometers increased in mass by 7.85 g, the amount of charge that had passed through it is 23,173 C.
<h3>Ionization of zinc</h3>
The zinc metal will ionize as shown below;
Zn²₊ + 2e⁻ → Zn
The molar mass of zinc metal is given as 65.38 g/mol
<h3>Amount of charge passed through 65.38 g/mol</h3>
Amount of charge that will deposite the given mass of zinc is calculated as follows;
e⁻ = 96500 C
2e⁻ = 2 x 96500 C = 193,000 C
<h3>Amount of charge passed through 7.85 g</h3>
65.38 g -------> 193,000 C
7.85 g -----------> ?
= (7.85 x 193,000)/(65.38)
= 23,173 C
Thus, when the zinc plate in one of Edison's coulometers increased in mass by 7.85 g, the amount of charge that had passed through it is 23,173 C.
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