Question

The number of atoms present in 100 grams of sodium is :

• A. $2.6182\times {10}^{23}$
• B. $0.6182\times {10}^{24}$
• C. $2.6182\times {10}^{24}$
• D. $2.6182\times {10}^{20}$

Answer 1

Answer: (C)

$2.6182\times {10}^{24}$

Atomic mass of Na = 23 gms

23 g of Na contains $6.022\times {10}^{23}$ number of atoms

Thus, 100 g of Na contains,

$\frac{6.022\times {10}^{23}}{23}\times 100$ number of atoms

$=2.6182\times {10}^{24}$.