Question

A copper plate of $10cm \times 10cm$ and $0.1cm$ thickness is to be plated with silver. If the density of Ag is $10.8g/cc$, then the number of moles of electrons required for this process is:
A.1 mole
B.2 mole
C.0.5 moles
D.2.5 moles

Answer 1

The process of applying metal coating on another conductive metal involving an electro-deposition process is called electroplating and this process is mostly used in decorative items or to prevent corrosion of a metal.

Complete step by step answer:
The area of the copper plate is given which is equal to $10 \times 10c{m^2} = 100c{m^2}$
And the thickness of the copper plate is given (t)=0.1 cm.
As we know the volume of copper plate = area×thickness
Hence $V = 100 \times 0.1 = 10c{m^3}$
Here density of silver is given which is equal to $10.8g/cc$
As we know $Density = \dfrac{{Mass}}{{Volume}}$
On putting the value in the above formula we will get:
$10.8 = \dfrac{{Mass}}{{10}}$
$\Rightarrow 10.8 \times 10 = Mass$
$\Rightarrow Mass = 108g$
Now we will calculate the number of moles of silver. As we know the number of moles can be calculated as given mass divided by molecular mass.
$Number{\text{ }}of{\text{ }}moles = \dfrac{{{\text{given mass}}}}{{{\text{molecular mass}}}}$
The molecular mass of a silver atom is 108 grams.
Hence the number of moles of silver=$\dfrac{{108}}{{108}} = 1{\text{ }}mol$
Hence $A{g^ + } + {e^ - } \to Ag$
As from above, we can say one mole of silver ion requires one mole of electrons. Hence the correct option is A.

Additional information: In addition to silver, we can utilize other materials for finishing such as gold and palladium. These materials are excellent in their tasks of providing finish but are a bit expensive compared to silver.

Note:
The silver coating is the best choice when it comes to the durable coating that lasts longer and also it is used in the aerospace industry. Silver coating of copper is widely used in industry as it improves thermal and electrical conductivity. Also Silver has anti-microbial properties and hence it is used in wearable medical devices to be used in hospitals.