Which of the following reacts vigorously with water?

Options

A. Sodium
B. Aluminiun
C. Copper
D. Iron

Explanation

To determine which of the following metals reacts vigorously with water, we can follow these steps:

### Step 1: Identify the Metals
First, we need to identify the metals listed in the options provided in the question. Common metals that are known to react with water include sodium, potassium, calcium, and magnesium.

### Step 2: Understand the Reactivity of Metals with Water
Next, we should understand the general reactivity of these metals with water:
- **Alkali Metals (e.g., Sodium, Potassium)**: These metals react vigorously with water, producing hydrogen gas and a corresponding metal hydroxide.
- **Alkaline Earth Metals (e.g., Calcium)**: These metals also react with water, but the reaction is less vigorous compared to alkali metals.
- **Transition Metals (e.g., Iron)**: Most transition metals do not react vigorously with water; some may react only with steam or at high temperatures.

### Step 3: Analyze the Reaction
For sodium:
- The reaction with water can be represented as:
\[ 2 \text{Na} + 2 \text{H}_2\text{O} \rightarrow 2 \text{NaOH} + \text{H}_2 \]
This reaction is vigorous and produces heat, which can ignite the hydrogen gas released.

For iron:
- Iron does not react vigorously with water under normal conditions. It may react with steam at high temperatures, but this is not considered vigorous.

### Step 4: Conclusion
Based on the analysis, we conclude that sodium is the metal that reacts vigorously with water.

### Final Answer
Sodium reacts vigorously with water.

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