Question

a sample of an oxide of antimony (sb) contain 19.75 g of antimony combine with 6.5 g of oxygen . what is the simplest formula for the oxide

Answer 1

Step-by-step explanation:

The given data is as follows.

Mass of antimony = 19.75 g

Molar mass of Sb = 121.76 g/mol

Therefore, calculate number of moles of Sb as follows.

Moles of Sb =
`\frac{mass}{\text{molar mass}}`

=
`(19.75 g)/(121.76 g/mol)`

= 0.162 mol

Mass of oxygen given is 6.5 g and molar mass of oxygen is 16 g/mol. Hence, moles of oxygen will be calculated as follows.

Moles of oxygen =
`\frac{mass}{\text{molar mass}}`

=
`(6.5 g)/(16 g/mol)`

= 0.406 mol

Hence, ratio of moles of Sb and O will be as follows

Sb : O

`(0.162)/(0.162) : (0.406)/(0.162)`

1 : 2.5

We multiply both the ratio by 2 in order to get a whole number. Therefore, the ratio will be 2 : 5.

Thus, we can conclude that the empirical formula of the given oxide is
`Sb_(2)O_(5)`.