Question

How many atoms are present in 49 g of $H_{2}S{O}_4$?

• A. $7\times 6.023\times {10}^{23}$
• B. $5\times 6.023\times {10}^{23}$
• C. $6\times 6.023\times {10}^{23}$
• D. $7\times 3.02\times {10}^{23}$

Answer 1

Answer: (D)

$7\times 3.02\times {10}^{23}$

Weight of $H_{2}S{O}_4=w=49g$

Molar mass of $H_{2}S{O}_4=M=98g/mol$

$\therefore$ number of moles of $H_{2}S{O}_4=n=\frac{w}{M}=\frac{49}{98}=0.5$

There are 7 atoms in the $H_{2}S{O}_4$

$\therefore$ total number of atoms $=7\times n\times 6.022\times {10}^{23}=7\times 0.5\times 6.022\times {10}^{23}=7\times 3.02\times {10}^{23}$

Hence, the correct option is $\left(D\right)$.