Q. 14.3( 230 Votes )
A 0.24 g sample of compound of oxygen and boron was found by analysis to contain 0.096 g of boron and 0.144 g of oxygen. Calculate the percentage composition of the compound by weight.
(i) Mass of boron in compound = 0.096 g
And, Mass of compound = 0.24 g
So, Percentage of boron =
= 40% (1)
(ii) Mass of oxygen in compound = 0.144 g
And, Mass of compound = 0.24 g
So, Percentage of oxygen =
= 60% (2)
Thus, the percentage composition of the compound is: Boron = 40%; Oxygen = 60%
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