Read the following and answer any four questions
During extraction of metals, electrolytic refining is used to obtain pure metals. During the process, the impure metal is made the anode and a thin strip of pure metal is made the cathode. The solution of the metal salt is used as an electrolyte. On passing the current through the electrolyte, the pure metal from the anode dissolves from the electrolyte. An equivalent of pure metal from the electrolyte is deposited on the cathode.
The anode is ________ and the reaction at the anode is ____________.

Options

A. negative, oxidation
B. negative, reduction
C. positive, oxidation
D. positive, reduction

Explanation

To answer the question, we need to fill in the blanks regarding the anode and the reaction that occurs at the anode during the electrolytic refining process.

### Step-by-Step Solution:

1. **Identify the Anode**: In the electrolytic refining process, the impure metal is made the anode. Therefore, the anode is the impure metal.

**Answer**: The anode is **impure metal**.

2. **Determine the Reaction at the Anode**: When current is passed through the electrolyte, the impure metal at the anode undergoes oxidation. Oxidation is defined as the loss of electrons. As the impure metal loses electrons, it dissolves into the electrolyte.

**Answer**: The reaction at the anode is **oxidation**.

3. **Complete the Sentence**: Now we can combine our findings to complete the sentence provided in the question.

**Final Answer**: The anode is **impure metal** and the reaction at the anode is **oxidation**.