The percentage mass composition of chlorine in HClO₃ is 42%.
Percentage mas of chlorine is calculated as follows:
atomic mass of chlorine = 35.5
(1) In HClO (gram-formula mass = 52 g/mol)
Percentage mass composition = 35 * 100% / 52 = 67.3%
(2) In HClO2 (gram-formula mass = 68 g/mol)
Percentage mass composition = 35 * 100%/68 = 51.4%
(3) HClO3 (gram-formula mass = 84 g/mol)
Percentage mass composition = 35 * 100% / 84 = 42%
(4) HClO4 (gram-formula mass = 100. g/mol)
Percentage mass composition = 35 * 100% / 100 = 35.5%
Therefore, the percentage mass composition of chlorine in HClO₃ is 42%.
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