Hydrogen at room temperature contains :

Options

A. `25%" ortho "+"75 % para"`
B. `"25% para "+"75% ortho"`
C. `"50% ortho "+"50% para"`
D. `"60% ortho "+"34% para"`

Answer

To solve the question regarding the composition of hydrogen at room temperature, we will follow these steps:

### Step 1: Understand the Forms of Hydrogen
Hydrogen exists in two different forms at room temperature: Ortho-hydrogen and Para-hydrogen.

### Step 2: Define Ortho and Para Forms
- **Ortho-hydrogen**: In this form, the spins of the two protons are aligned in the same direction.
- **Para-hydrogen**: In this form, the spins of the two protons are aligned in opposite directions.

### Step 3: Determine the Proportions
At room temperature, the typical proportions of these two forms of hydrogen are approximately:
- **75% Ortho-hydrogen**
- **25% Para-hydrogen**

### Step 4: Analyze the Options
Given the options:
- Option A: 60% Ortho and 34% Para
- Option B: 50% Ortho and 50% Para
- Option C: 25% Para and 75% Ortho
- Option D: 75% Ortho and 25% Para

From our understanding, the correct proportions are 75% Ortho and 25% Para.

### Step 5: Identify the Correct Answer
The correct answer is:
- **Option D: 75% Ortho and 25% Para**

### Final Conclusion
Thus, hydrogen at room temperature contains 75% Ortho-hydrogen and 25% Para-hydrogen.

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