Question

A certain mass of sulfur required $16$ grams of oxygen to be converted into sulfer dioxide, $S{O}_2$. If this same mass of sulfur was to be converted into suffer trioxide, $S{O}_3$, the mass of oxygen required would be:

• A. $4.0g$
• B. $8.0g$
• C. $12g$
• D. $24g$
• E. $32g$

Answer 1

The correct option is D $24g$

Atomic weight of Sulphur is 32 grams. Atomic weight of Oxygen is 16 grams.

Molecular weight of $S{O}_2$ is 64 grams.

32 grams of Oxygen reacts with 32 grams of Sulphur to produce $S{O}_2$

1 gram of Oxygen will react with $\frac{32}{32}$ gram of Sulphur

Thus 16 grams of Oxygen will react with 16 grams of Sulphur to produce $S{O}_2$

Now, this 16 grams of Sulphur will be converted to one mole of Sulphur Trioxide.

32 grams of Sulphur requires 48 grams of Oxygen to produce $S{O}_3$

1 gram of Sulphur requires $\frac{48}{32}$ grams of Oxygen

Thus, 16 grams of Sulphur will require 24 Grams of Oxygen (by unitery method)