The boiling point of liquid hydrogen is

Options

A. `2.53^@ C`
B. `25.3^@ C`
C. `252^@`C
D. `-253^@ C`

Explanation

To find the boiling point of liquid hydrogen, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Chemical Formula**:
- The chemical formula for hydrogen in its molecular form is \( H_2 \).

2. **Determine the Molar Mass**:
- The molar mass of \( H_2 \) is approximately \( 2.016 \, \text{g/mol} \).

3. **Understand the Physical Properties**:
- Liquid hydrogen is a colorless liquid with a density of \( 70.85 \, \text{g/L} \).
- It has a melting point of \( -259.14 \, \text{°C} \).

4. **Find the Boiling Point**:
- The boiling point of liquid hydrogen is given as \( -252.87 \, \text{°C} \).

5. **Approximate the Boiling Point**:
- Rounding \( -252.87 \, \text{°C} \) gives approximately \( -253 \, \text{°C} \).

6. **Select the Correct Option**:
- From the provided options:
1. \( 2.53 \, \text{°C} \)
2. \( 25.3 \, \text{°C} \)
3. \( -252.0 \, \text{°C} \)
4. \( -253 \, \text{°C} \)
- The correct answer is option 4: \( -253 \, \text{°C} \).

### Final Answer:
The boiling point of liquid hydrogen is approximately \( -253 \, \text{°C} \).

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