Metals of how many groups of periodic table show maximum catalytic activity.

Answer

To solve the question of how many groups of the periodic table show maximum catalytic activity, we can follow these steps:

### Step 1: Identify the Relevant Groups
We need to focus on the transition metals, which are located in the d-block of the periodic table. These metals are known for their catalytic properties.

**Hint:** Transition metals are primarily found in groups 3 to 12 of the periodic table.

### Step 2: Understand Catalytic Activity
Catalytic activity is the ability of a substance to increase the rate of a chemical reaction without being consumed in the process. Transition metals are effective catalysts because they can easily form complexes with reactants.

**Hint:** Consider how the ability to form different oxidation states and complexes contributes to catalytic activity.

### Step 3: Analyze Groups for Maximum Activity
From the information provided, we know that catalytic activity increases as we move from group 5 to group 11. Specifically, groups 7, 8, and 9 are highlighted as those showing maximum catalytic activity.

**Hint:** Look for patterns in the periodic table that indicate which groups are most effective as catalysts.

### Step 4: Count the Groups
The groups that show maximum catalytic activity are:
- Group 7
- Group 8
- Group 9

This gives us a total of three groups.

**Hint:** Ensure you list out the groups clearly to avoid confusion.

### Final Answer
The total number of groups in the periodic table that show maximum catalytic activity is **3** (Groups 7, 8, and 9).

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