Question

If 10^20 molecules are removed from 50mg N2O no. Of moles of N2O left approximately

Answer 1

Molar mass of N2O is 44g
1mole=6.023×10^23 particles

44g=6.023×10^23 particles
50g= x
by cross multiplication
44x=(6.023×10^23)(50)
x=6.843×10^23 particles in 50g(total)

Now remove 10^20 particles from total particles

=6.843×10^23 - 10^20
=6.843×10^3(remaining)

Convert it into moles

1 mole =6.023×10^23 particles
x =6.843×10^3 particles
By cross multiplication
1.14 moles is your answer