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Question
Give the chemical formulae for the following compounds and compute the ratio by mass of the combining elements in each one of them. (You may use appendix-III).
- Ammonia
- Carbon monoxide
- (Hydrogen chloride
- Aluminium fluoride
- Magnesium sulphide
Solution
| Chemical formula | Ratio by mass | |
| (a) | Ammonia (NH3) | N(I) : H(3) 14 : 3 |
| (b) | Carbon monoxide (CO) | C(1) : O(1) 12 : 16 or 3 : 4 |
| (c) | Hydrogen chloride (HCl) | H(1) : Cl(I)1 : 23.5 or 2 : 71 |
| (d) | Aluminium fluoride (AlF3) | Al(1) : F(3) 27 : 19 × 3 or 9 : 19 |
| (e) | Magnesium sulphide (MgS) | Mg(1) : S(1) 24 : 32 or 3 : 4 |
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