Question

4.8 g of magnesium on burning with same amount of oxygen gives magnesium oxide. Calculate the amount of product formed.

• A. 6 g
• B. 4 g
• C. 12 g
• D. 8 g

Answer 1

Answer: (D)

8 g

The chemical equation can be written as:
$2Mg+O_2\to 2MgO$
48 g of Mg reacts with 32 g of $O_2$.
Thus, 4.8 g of $Mg$ reacts with 3.2 g of $O_2$.
Now, 32 g of $O_2$ forms = 80 g of $MgO$.
3.2 g of $O_2$ produces = $\frac{80}{32}\times 3.2$ = 8 g of $MgO$.