Question

Consider the below statements and identify the correct answer.

1. Statement-1: On heating, the surface of copper powder becomes coated with black copper (II) oxide.
2. Statement-II: If hydrogen gas is passed over this heated material (CuO), the black coating on the surface tums brown.

• A. 2 only
• B. All of these
• C. None of these
• D. 1, 2

Answer 1

Answer:

B. All of these

• Statement I is true

• Because when copper is heated in air, it reacts with oxygen to form copper(II) oxide (CuO), which is black in color.

• Statement II is also true

• Because when hydrogen gas is passed over heated copper(II) oxide, the hydrogen reduces the copper(II) oxide to copper, which is brown in color.