Question

Calculate the percent composition of Cr2O3

Answer 1

Cr 2(52.0) = 104 O 3(16.0) = 48
104/152 * 100 = 68.42% Cr
48/152 * 100 = 31.58% O

Answer 2

Step-by-step explanation:

Percentage of an element in a compound:

`\frac{\text{Number of atoms of element}* \text{Atomic mass of element}}{\text{molecular mass of compound}}* 100`

Molecular mass of
`Cr_2O_3` = 152 g/mol

Percentage of chromium:

Number of chromium atoms = 2

Atomic mass of chromium = 52 g/mol

`(2* 52g/mol)/(152g/mol)* 100=68.42\%`

Percentage of oxygen:

Number of oxygen atoms = 3

Atomic mas of oxygen = 16 g/mol

`(3* 16g/mol)/(152 g/mol)* 100=31.58\%`

The percent composition of Cr in
`Cr_2O_3` is 68.42%.

The percent composition of O in
`Cr_2O_3` is 31.58%.