Question

How many silver atoms are there in $2.00{\text{ moles}}$ of silver?

Answer 1

We know that the amount of substance having exactly the same number of atoms as are present in $12{\text{ g}}$ of ${{\text{C}}^{{\text{12}}}}$ is known as mole. Moles is the ratio of the mass of substance in g to the molar mass of the substance in ${\text{g/mol}}$. ${\text{1 mol}}$ of any substance contains $6.022 \times {10^{23}}$ atoms. $6.022 \times {10^{23}}$ is Avogadro's number.

Complete solution:
We know that the amount of substance having exactly the same number of atoms as are present in $12{\text{ g}}$ of ${{\text{C}}^{{\text{12}}}}$ is known as mole. Moles is the ratio of the mass of substance in g to the molar mass of the substance in ${\text{g/mol}}$. ${\text{1 mol}}$ of any substance contains $6.022 \times {10^{23}}$ atoms. $6.022 \times {10^{23}}$ is Avogadro's number.
We know that ${\text{1 mol}}$ of any substance contains $6.022 \times {10^{23}}$ atoms. We are given $2.00{\text{ moles}}$ of silver. Thus,
Number of silver atoms $= 2{\text{ mol}} \times \dfrac{{6.022 \times {{10}^{23}}{\text{ atoms}}}}{{1{\text{ mol}}}}$
Number of silver atoms $= 12.044 \times {10^{23}}{\text{ atoms}}$
Thus, $2.00{\text{ moles}}$ of silver contains $12.044 \times {10^{23}}{\text{ atoms}}$ of silver.

Additional Information: The Avogadro’s number is named after the scientist Amedeo Avogadro who discovered it. The Avogadro’s number is also known as Avogadro’s constant. It is denoted by ${N_A}$. The Avogadro’s number is the proportionality factor that relates the number of constituent particles i.e. the number of molecules or atoms or ions in one mole of a substance. The Avogadro’s constant is a dimensionless number.

Note: The number of atoms of a compound is Avogadro’s number for 1 mole of compound. The number $6.022 \times {10^{23}}$ is known as Avogadro’s number. The Avogadro’s number gives the number of atoms, ions or molecules present in one mole of any substance.