The ratio of oxygen to carbon by mass in carbon monoxide is 1.33: 1.00. part a find the formula of an oxide of carbon in which the ratio by mass of oxygen to carbon is 2.00: 1.00.

To calculate the molecular formula, convert the mass ratio into molar ratio as follows:

mass ratio of O:C=2:1

molar mass of carbon is 12 g/mol and that of oxygen is 16 g/mol thus, number of moles can be calculated as follows:

n=\frac{m}{M}

calculating ratio,

O:C=\frac{2 g}{16 g/mol}:\frac{1 g}{12 g/mol}=\frac{1}{8}:\frac{1}{12}=12:8=3:2

thus, molecular formula will be C_{2}O_{3}