The one with maximum oxidising power is

Options

A. Hypochlorous acid
B. Chlorous acid
C. Chloric acid
D. Perchloric acid

Answer

To determine which of the given acids has the maximum oxidizing power, we need to analyze the oxidation states of chlorine in each acid. The acids provided are:

1. Hypochlorous acid (HClO)
2. Chlorous acid (HClO2)
3. Chloric acid (HClO3)
4. Perchloric acid (HClO4)

### Step-by-Step Solution:

**Step 1: Identify the oxidation states of chlorine in each acid.**

- For hypochlorous acid (HClO):
- The oxidation state of chlorine (Cl) is +1.

- For chlorous acid (HClO2):
- The oxidation state of chlorine (Cl) is +3.

- For chloric acid (HClO3):
- The oxidation state of chlorine (Cl) is +5.

- For perchloric acid (HClO4):
- The oxidation state of chlorine (Cl) is +7.

**Step 2: Determine the tendency to act as an oxidizing agent.**

- The oxidizing power of an element is generally higher when it has a lower oxidation state. This is because species with lower oxidation states have a greater tendency to lose electrons (get oxidized) and thus can oxidize other substances.

**Step 3: Compare the oxidation states.**

- The oxidation states we found are:
- HClO: +1
- HClO2: +3
- HClO3: +5
- HClO4: +7

- Among these, the lowest oxidation state is +1 in hypochlorous acid (HClO).

**Step 4: Conclude which acid has the maximum oxidizing power.**

- Since hypochlorous acid (HClO) has the lowest oxidation state of chlorine (+1), it has the maximum oxidizing power compared to the other acids listed.

### Final Answer:
The acid with the maximum oxidizing power is **hypochlorous acid (HClO)**.

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