Question

Calculatethe molecular masses of H₂,O₂,Cl₂,CO₂,CH₄,C₂H₆,C₂H₄,NH₃,CH₃OH.

Answer 1

Molecularmass of H₂= 2 ×Atomic mass of H

=2 ×1

= 2 u

Molecularmass of O₂= 2 ×Atomic mass of O

=2 ×16

= 32 u

Molecularmass of Cl₂= 2 ×Atomic mass of Cl

=2 ×35.5

= 71 u

Molecularmass of CO₂= Atomic mass of C + 2 ×Atomic mass of O

=12 + 2 ×16

= 44 u

Molecularmass of CH₄= Atomic mass of C + 4 ×Atomic mass of H

=12 + 4 ×1

= 16 u

Molecularmass of C₂H₆= 2 ×Atomic mass of C + 6 ×Atomic mass of H

=2 ×12 + 6 ×1

=30 u

Molecularmass of C₂H₄= 2 ×Atomic mass of C + 4 ×Atomic mass of H

=2 ×12 + 4 ×1

= 28 u

Molecularmass of NH₃= Atomic mass of N + 3 ×Atomic mass of H

=14 + 3 ×1

= 17 u

Molecular mass of CH₃OH= Atomic mass of C + 4 ×Atomic mass of H + Atomic mass of O

=12 + 4 ×1 + 16

=32 u