Pick the odd one out

Options

A. Sodium borohydride reacts very slowly with cold water
B. Sodium borohydride reacts very violently with cold water to produce `H_(2)`
C. Solubility of sodium borohydride in water at `25^(@)C` is `10.5 g // mL`
D. Melting point of sodium borohydride is `500^(@)C`

Explanation

To solve the question "Pick the odd one out," we will analyze the three statements provided about sodium borohydride (NaBH4) and identify which one is incorrect.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The first statement claims that sodium borohydride reacts very slowly with cold water.
- This statement is true. Sodium borohydride does indeed react slowly with cold water.

2. **Analyze the Second Statement:**
- The second statement claims that sodium borohydride reacts very violently with cold water to produce hydrogen gas (H2).
- This statement is false. Sodium borohydride does not react violently with cold water; it reacts slowly instead.

3. **Analyze the Third Statement:**
- The third statement mentions that the solubility of sodium borohydride in water is 10.5 g per mL.
- This statement is true. The solubility of sodium borohydride in water is indeed around 10.5 g per mL.

4. **Identify the Odd One Out:**
- From the analysis, we find that the first and third statements are true, while the second statement is false.
- Therefore, the odd one out is the second statement, which incorrectly describes the reaction of sodium borohydride with cold water.

### Final Answer:
The odd one out is the second statement: "Sodium borohydride reacts very violently with cold water to produce H2."

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