An analysis of pyrex glass showed 12.9% `B_(2)O_(3),2,2% Al_(2)O_(3).3.8% Na_(2)O,0.4% K_(2)O` and remaining is `SiO_(2)`. What is the ratio of silicon to boron atoms in the glass?

Explanation

Percentage composition of `B_(2)O_(3)=12.9%`
Percentage composition of
`SiO_(2)=100-[12.9+2.2+3.8+0.4]`
=80.7%
Number of moles of `B_(2)O_(3)=("Mass")/("Molar mass")=(12.9)/(70)=0.184`
Number of moles of boron atoms `=2xx0.184`
Number of moles of `SiO_(2)=("Mass")/("Molar mass")=(80.7)/(60)=1.345`
Number of moles of silicon atoms =1.345
`("Number of atoms of silicon")/("Number of atoms of boron")=(N_(A)xx1.345)/(N_(A)xx0.184)=(7.3)/(1)`
Where `N_(A)=` Avogadro's number.