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Question
Write the name of the following compound and deduce its molecular mass.
CO2
Solution
CO2 - Carbon dioxide
| Molecule | Constituent elements | Atomic mass u | Number of atoms in the molecule | Atomic mass × number of atoms | Mass of the Constituents u |
| CO2 | C | 12 | 1 | 12 × 1 | 12 |
| O | 16 | 2 | 16 × 2 | 32 |
The molecular mass of CO2 = Sum of Constituent atomic masses
(Molecular mass of CO2) = (Atomic mass of C) × 1 + (Atomic mass of O) × 2
= (12 × 1) + (16 × 2)
= 12 + 32
= 44 u
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