No. of oxygen atoms in 20g of sulphur trioxide `(SO_(3))`
Molar mass of `SO_(3)=32+3xx16=80g`
80g of `SO_(3)` have oxygen atoms=`3xxN_(A)`
20g of `SO_(3)` have oxygen atoms= `=(3xxN_(A)xx(20g))/((80g))=0.75N_(A)`
Step-II: Mass (X) of ozone having same no. of oxygen atoms
`"Molar mass of "O_(3)=3xx16=48g`
`3xxN_(A)"oxygen atoms are present in ozone"=48g`
`0.75xxN_(A)"oxygen atoms are present in ozone"=(48g )xx(10.75xxN_(A))/((3xxN_(A)))=12g`
`therfore X=12g`