Question

How many oxygen atoms are present in 22g of CO2 ?? ☺☺☺

Answer 1

First you need to find relative molecular mass. You can calculate it using relative atomic mass of C and O So

MCO2=12+16×2

=44gmol−1

molecular mass of CO2 is 44. Which mean 44 grams of CO2contain Avogadro’s number of atoms. So,

44gmol−1=6.022×1023mol−1(Avogadro’s number)

442=6.022×10232

22g=3.011×1023

So 22g of CO2have 3.011×1023 CO2molecules.

Since one molecule has one carbon atom it also has 3.011×1023 Carbon atoms

Answer 2

molar mass of CO2=12+16×2=12+32=44gm
so in 44gm of CO2 2 oxygens are present
hence in 22 gm no. of O atom=22×2/44=1