JEE Chemistry 2024 Question with Solution

Given: $1$ mole of $\text{PbS}$ is oxidized by ozone.

Find: $X + Y$, where $X$ is the moles of $\text{O}_3$ used and $Y$ is the moles of $\text{O}_2$ formed.

From the balanced reaction:

$$\text{PbS} + 4\text{O}_3 \rightarrow \text{PbSO}_4 + 4\text{O}_2$$

So, for $1$ mole of $\text{PbS}$:

• $X = 4$
• $Y = 4$

Therefore,

$$X + Y = 4 + 4 = 8$$

Hence, the required value is $8$.

Given: the balanced equation

$$\text{PbS} + 4\text{O}_3 \rightarrow \text{PbSO}_4 + 4\text{O}_2$$

Find: $X + Y$.

Read the coefficients directly from the balanced equation for $1$ mole of $\text{PbS}$. The coefficient of $\text{O}_3$ gives $X = 4$ and the coefficient of $\text{O}_2$ gives $Y = 4$.

So,

$$X + Y = 4 + 4 = 8$$

Therefore, the answer is $8$.