Question

Glucose is a carbohydrate that contains carbon, hydrogen, and oxygen. The empirical formula of glucose is CH2O and its molar mass is 180.12 g/mol. Find the molecular formula of glucose.

Answer 1

Answer: The molecular formula of glucose is
`C_6H_(12)O_6`

Step-by-step explanation:

We are given:

Empirical formula of the compound =
`CH_2O`

Empirical mass of the compound =
`[(1* 12)+(2* 1)+(1* 16)]=30g/mol`

For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.

The equation used to calculate the valency is:

`n=\frac{\text{Molecular mass}}{\text{Empirical mass}}`

We are given:

Mass of molecular formula = 180.12 g/mol

Mass of empirical formula = 30 g/mol

Putting values in above equation, we get:

`n=(180.12g/mol)/(30g/mol)=6`

Multiplying this valency by the subscript of every element of empirical formula, we get:

`C_((1* 6))H_((2* 6))O_((1* 6))=C_6H_(12)O_6`

Hence, the molecular formula of glucose is
`C_6H_(12)O_6`