Question

The number of oxygen atoms in 20 gm of sulphur tri-oxide ${SO}_3$ is the same as these present in x gms of Ozone. The atomic mass of sulphur and oxygen are 32 $\mu$ and 16 $\mu$ respectively. Find the value of $\mu$. (12 gm)

Answer 1

Molar mass of the sulpheric trioxide is $32+2\times 16=80g/mol$

Number of grams of $O$ in $80g/mol$ in $S{O}_3=48g$

Number of grams of $O$ in $20g/mol$ in $S{O}_3=\frac{48}{80}\times 20$

$=12g$

Number of moles in 12 oxygen$=\frac{12}{16}=0.75$

No of atoms in 0.75 moles of oxygen is

$0.75\times 6.0\times {10}^{23}$

$=4.515\times {10}^{23}$

Now, The molar mass of the Ozone is $O_3=3\times 16=48g$

Since $6.02\times {10}^{23}$atoms make $48g$ Ozone $4.515\times {10}^{23}$ atoms make

$=\frac{48}{6.022\times {10}^{23}}\times 4.515\times {10}^{23}$

$=36g$ of Ozone