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Question
Work out the formula for sulphur dioxide. (Valencies : S = 4 ; O = 2)
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Solution
Valency of Sulphur = 4
Valency of Oxygen = 2
Elements : S O
Valencies : 4 2
Formula for sulphur dioxide can be worked out by crossing the valencies of the constituent elements.
Thus, formula of sulphur dioxide is S2O4. The formula has a common factor of 2; therefore, dividing the formula by the common factor gives us the simplest chemical formula: SO2.
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