Q5 of 29 Page 85

0.24g sample of compound of oxygen and boron was found by analysis to contain 0.144g of oxygen and 0.096g of boron. Calculate the percentage composition of the compound by weight.

Given: Mass of compound = 0.24g


Mass of oxygen = 0.144g


Mass of boron = 0.096g


To calculate the percent of the composition of oxygen, we apply the formula:



⇒


⇒ % composition of oxygen = 0.6g × 100


⇒ % composition of oxygen = 60%


To calculate the percent of the composition of boron, we apply the formula:



⇒


⇒ % composition of boron = 0.4g × 100


⇒ % composition of boron = 40%


Total percentage composition of compound is 60% + 40% = 100%


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