<u>Answer:</u> The amount of zinc required are 0.0118 moles
<u>Explanation:</u>
To calculate the number of moles, we use the equation:

Given mass of silver nitrate = 4 g
Molar mass of silver nitrate = 169.9 g/mol
Putting values in above equation, we get:

The chemical equation for the reaction of zinc and silver nitrate follows:

By Stoichiometry of the reaction:
2 moles of silver nitrate reacts with 1 mole of zinc
So, 0.0235 moles of silver nitrate will react with =
of zinc
Hence, the amount of zinc required are 0.0118 moles