Question

calculate the mass of aluminium present in 34g of aluminium oxide​

Answer 1

Given: 34g of aluminium oxide.

To find: We have to find the mass of Al.

Solution:

The formula of aluminium oxide is $Al_2O_3$.

The atomic mass of Al is 27 and the atomic mass of Oxygen is 16.

Thus, the molecular weight of aluminium chloride is

$27 \times 2 + 16 \times 3 \\ = 54 + 48 \\ = 102$

Thus 102 grams of aluminium oxide has 54 grams of Al.

34 grams of aluminium oxide will have-

$\frac{34 \times 54}{102} \\ 18$

The mass of aluminium present in 34g of aluminium oxide is 18grams.