The fast reaction between water and sodium is the example is -

Options

A. Oxidation
B. Reduction
C. Redox
D. none

Answer

To solve the question regarding the reaction between water and sodium, we will analyze the reaction step by step.

### Step 1: Write the chemical equation for the reaction
The reaction between sodium (Na) and water (H₂O) can be represented as:
\[ 2 \text{Na} + 2 \text{H}_2\text{O} \rightarrow 2 \text{NaOH} + \text{H}_2 \]

### Step 2: Identify the oxidation states
Next, we need to determine the oxidation states of the elements involved in the reaction:
- Sodium (Na) in its elemental form has an oxidation state of 0.
- In sodium hydroxide (NaOH), sodium has an oxidation state of +1.
- In water (H₂O), hydrogen has an oxidation state of +1 and oxygen has an oxidation state of -2.
- In the hydrogen gas (H₂) produced, hydrogen has an oxidation state of 0.

### Step 3: Determine oxidation and reduction
Now, we can identify which elements are oxidized and which are reduced:
- Sodium (Na) goes from an oxidation state of 0 to +1. This is an increase in oxidation state, indicating that sodium is oxidized.
- Hydrogen in water (H₂O) goes from +1 to 0 in the formation of H₂. This is a decrease in oxidation state, indicating that hydrogen is reduced.

### Step 4: Classify the reaction
Since both oxidation (sodium) and reduction (hydrogen) occur in the same reaction, we classify this reaction as a redox reaction.

### Conclusion
Thus, the reaction between water and sodium is an example of a redox reaction. Therefore, the correct answer is option C.

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