Question

Calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 7.1 g. Silver has 47 electrons per atom, and its molar mass is 107.87 g/mole.

Answer 1

Answer: The number of electrons in given amount of silver are $1.87\times 10^{24}$

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

We are given:

Given mass of silver = 7.1 g

Molar mass of silver = 107.87 g/mol

Putting values in above equation, we get:

$\text{Moles of silver}=\frac{7.1g}{107.87g/mol}=0.066mol$

Number of electrons in 1 atom of silver = 47

According to mole concept:

1 mole of an element contains $6.022\times 10^{23}$ number of particles

So, 0.066 moles of silver will contain = -$(0.066\times 47\times 6.022\times 10^{23})=1.87\times 10^{24}$ number of electrons

Hence, the number of electrons in given amount of silver are $1.87\times 10^{24}$