Two samples of sodium chloride were decomposed into their constituent elements. one sample produced 4.65 g of sodium and 7.16 g of chlorine, and the other sample produced 7.45 g of sodium and 11.5 g of chlorine. are these results consistent with the law of constant composition? explain your answer.

Respuesta :

1) m(Na) = 4.65 g.

n(Na) = m(NA) ÷ M(Na).

n(Na) = 4.65 g ÷ 23 g/mol.

n(Na) = 0.202 mol.

m(Cl₂) = 7.16 g.

n(Cl₂) = 7.16 g ÷ 70.9 g/mol.

n(Cl₂) = 0.101 mol → n(Cl) = 2 · n(Cl₂) = 0.202 mol.

In sodium chloride (NaCl) proportion of sodium and chlorine atoms are:

n(Na) : n(Cl) = 1 : 1.

In this example n(Na) : n(Cl) = 0.202 mol : 0.202 mol (1 : 1).

2) n(Na) = 7.45 g ÷ 23 g/mol.

n(Na) = 0.324 mol.

n(Cl₂) = 11.5 g ÷ 70.9 g/mol.

n(Cl₂) = 0.162mol → n(Cl) = 0.324 mol.

n(Na) : n(Cl) = 1 : 1; results consistent with the law of constant composition.