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Question
An element B shows valencies of 4 and 6. Write the formulae of its two oxides.
Solution
Case i
Valency of B = 4
Valency of O = 2
Elements : B O
Valencies : 4 2
Formula for the oxide formed by the element B (valency 4) can be worked out by crossing over the valencies of the constituent elements.
Therefore, formula of the oxide of element B is B2O4. The formula has a common factor of 2; hence, dividing the formula by the common factor gives us the simplest chemical formula: BO2.
Case ii
Valency of element B = 6
Valency of O = 2
Formula for the oxide formed by the element B (valency 6) can be worked out by crossing over the valencies of the constituent elements.
Therefore, formula of the oxide of element B is B2O6. The formula has a common factor of 2; therefore, dividing the formula by the common factor gives us the simplest chemical formula: BO3.
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