Question

which impurity found in coal can lead to acid rain in the atmosphere? sulfur lead oxygen hydrogen

Explanation:

When coal burns, sulfur reacts with oxygen to form sulfur dioxide ($\text{SO}_2$). Sulfur dioxide can further react in the atmosphere to form sulfuric acid ($\text{H}_2\text{SO}_4$), which is a major component of acid rain. Lead is a toxic heavy - metal impurity in coal but does not directly contribute to acid rain. Oxygen is a major component of air and is not an impurity in the context of causing acid rain from coal. Hydrogen in coal, when burned, forms water ($\text{H}_2\text{O}$) and does not contribute to acid rain.

Answer:

sulfur