Which of the following will not act as oxidising agents?

Options

A. `CrO_(3)`
B. `MoO_(3)`
C. `WO_(3)`
D. `CrO_(4)^(2-)`

Explanation

To determine which of the given species will not act as an oxidizing agent, we need to understand the characteristics of oxidizing agents. Here’s a step-by-step solution:

### Step 1: Define Oxidizing Agents
An oxidizing agent is a substance that can accept electrons from another species during a chemical reaction. This means that the oxidizing agent itself gets reduced while the other species gets oxidized.

### Step 2: Identify Oxidation States
Oxidizing agents typically have a high oxidation state, which can be reduced to a more stable lower oxidation state. Therefore, we need to look at the oxidation states of the given species.

### Step 3: Analyze the Given Species
Let's consider the species mentioned in the question (for example, CrO3, Mo, W, etc.) and their oxidation states:
- **CrO3**: Chromium in CrO3 has an oxidation state of +6.
- **Molybdenum (Mo)**: Molybdenum can exist in various oxidation states, including +6.
- **Tungsten (W)**: Tungsten also has a +6 oxidation state.
- **Other species**: If there are other species mentioned, we would analyze their oxidation states similarly.

### Step 4: Determine Stability of Lower Oxidation States
Next, we need to determine the stability of the lower oxidation states for each of these elements:
- **Chromium**: The +6 oxidation state is relatively stable and does not readily convert to a lower oxidation state.
- **Molybdenum and Tungsten**: Both of these elements have lower oxidation states that are more stable compared to their +6 state, making them good oxidizing agents.

### Step 5: Conclusion
Based on the analysis, we conclude that:
- **CrO3** will not act as an oxidizing agent because its +6 oxidation state is stable and does not want to be reduced to a lower oxidation state.
- **Molybdenum and Tungsten** will act as oxidizing agents because they can be reduced to more stable lower oxidation states.

### Final Answer
Thus, the species that will not act as an oxidizing agent is **CrO3**.

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