Question

How many spoons can be electroplated by silver when 5 ampere current is passed through electrolytic cell of AgNo3 for 2.5 hours? Efficiency of the cell is 80 % and 0.01 gram Ag layer is deposited on each spoon (Ag-108 gm/mole).

Answer 1

For every 96485 columb of charge 108gm of Ag will be deposited.

In 2.5 hours 750*80%=600 C is passed.

Therefore amount of Ag is (600/96485)*108 =0.671gm

No. Of spoons is 67

Answer 2

Answer:

4029 spoons can be electroplated.

Explanation:

The charge can be calculated using the formula

Q = I×t

Substituting the values

Q = 5×2.5×3600×0.80

   = 36000 C

One mole of electron charge has 96500 C.

Thus, the number of moles in 36000 C = $\frac{36000}{96500}$ =0.37305 moles

One mole of charge is equivalent to one mole of silver.

0.37305 mole of charge is equivalent to 0.37305 moles of silver.

Total mass of silver = moles× molecular weight

                                = 0.37305×108

                                = 40.2894

$Number of spoons = \frac{Total weight of silver}{silver weight of one spoon}$

                             $= \frac{40.2894}{0.01}$

                             =4029 spoons