The density of Cu is 8.94 g cm^–3. The quantity of electricity needed to plate an area 10 cm x 10 cm to a thickness of 10^–2 cm using CuSO₄ solution would be

27155 C

The correct answer is option 2. 27155 C.

The quantity of electricity required to plate the given area and thickness using the correct calculations.

Given:

Density of Cu = \(8.94 g cm^{-3}\)

Area = 10 cm × 10 cm = \(100 cm^2\)

Thickness = \(10^{-2} cm\)

To calculate the quantity of electricity, we need to determine the weight of copper deposited.

Weight of copper deposited = Area × Thickness × Density = \(100 cm^2 × 10^{-2} cm × 8.94 g cm^{-3}\) = \(8.94 g\)

Next, we need to convert the weight of copper to moles using its molar mass.

Molar mass of Cu = \(63.55 g/mol\)

\(\text{Moles of Cu = }\frac{Weight}{Molar mass} = \frac{8.94 g }{ 63.55 g/mol} \approx 0.1407 mol\)

The number of Faradays needed to deposit 1 mole of Cu is two.

Therefore, the quantity of electricity required can be calculated as follows:

\(\text{Quantity of electricity = Moles } \times \text{Faraday's constant = }0.1407 mol \times 2 \times 96500 C/mol \approx 27155 C\).

Therefore, the correct answer is (2) 27155 C.