Question

Calculate the molar mass of : (a) Ethyne

Answer 1

(a) Ethyne

1. Molar mass is the sum of the masses of all the individual atoms present in a molecule or compound
2. The atomic mass of carbon C is 12u.
3. The atomic mass of hydrogen H is 1u.
4. The atomic mass of Phosphorous is 31u.
5. The atomic mass of sulphur is 32u.
6. The atomic mass of Nitrogen is 14u.
7. The atomic mass of Oxygen is 16u.
8. The chemical formula of Ethyne ${\mathrm{C}}_2{\mathrm{H}}_2$
9. $\mathrm{Molar}\mathrm{mass}\mathrm{Ethyne}\left({\mathrm{C}}_2{\mathrm{H}}_2\right)=(\mathrm{Atomic}\mathrm{mass}\mathrm{of}\mathrm{carbon})\mathrm{x}2+(\mathrm{Atomic}\mathrm{mass}\mathrm{of}\mathrm{hydrocarbon})\mathrm{x}2$

$=(12\mathrm{x}2)+(1\mathrm{x}2)$

$=24+2$

$=26\mathrm{g}$

The molar mass of ethyne $\left({\mathrm{C}}_2{\mathrm{H}}_2\right)$ is 26g.