How many atoms are in a sample of 175 g of sodium (Na)?

Question:

How many atoms are in a sample of {eq}175 \, \mathrm{g} {/eq} of sodium ({eq}\mathrm{Na} {/eq})?

Mole Concept

Mole is the fundamental unit of the amount of substance. It is also called Avogadro's number and represented by {eq}N_{A} {/eq}. A mole is equal to as many particles as there in the one-twelfth mass of the C-12 atom.

Number of atoms is given by the formula,

{eq}Number\,of\,atoms\, = \frac{Mass}{Molar \, mass} \times 6.022 \times 10^{23} \\ Number\,of\,atoms\, = \frac{175}{23} \times 6.022 \times 10^{23} \\ Number\,of\,atoms\, = 4.58 \times 10^{24} {/eq}