If the cost of electricity required to discharge 10g of an ion X\(^{3+}\) is N20.00, how much would it cost to discharge 6g of ion Y\(^{2+}\)?
[1 faraday = 96,500C, atomic masses are X = 27, Y = 24]
- N10.00
- N6.00
- N20.00
-
N9.00
The correct answer is: D
Explanation
X\(^{3+}\) + 3e\(^-\) \(\to\) X
3F = 27g
xF = 10g
\(\frac{x}{3} = \frac{10}{27} \implies x = \frac{10}{9} F\)
\(\frac{10}{9}\)F \(\equiv\) N20.00
1F is equivalent to x
\(\frac{1}{\frac{10}{9}} = \frac{x}{20}\)
\(\frac{9}{10} = \frac{x}{20} \implies x = N18.00\)
1F is equivalent to N18.00.
Y\(^{2+}\) + 2e\(^-\) \(\to\) Y
2F = 24g
xF = 6g
x = \(\frac{6 \times 2}{24} = \frac{1}{2} F\)
1F = N18.00
\(\frac{1}{2}\)F = \(\frac{1}{2} \times N18.00\)
= N9.00
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