a 7.221 g sample of a compound contains 1.990 g carbon, 2.341 g hydrogen, and the rest is oxygen. Determine the
percent composition of the compound

Respuesta :

Answer:

17.19%

Explanation:

mass of oxygen = 7.221 - (1.990 + 2.341)

= 2.890g

Empirical formula of the compound

For carbon,

1.990/12 = 0.1658

For hydrogen,

2.341/1 = 2.341

For oxygen,

2.890/16 = 0.1806

0.1658 ÷ 0.1658 = 1

2.341 ÷ 0.1658 = 14.11

0.1806 ÷ 0.1658 = 1.089

Empirical formula of the compound= CH14O

Molar mass= (1×12) + (14×1) + (1×16)

= 12+14+16

= 42g/mol

percentage composition= 7.221/42 × 100

= 17.19%