A gas cylinder can hold 1 kg of hydrogen at room temperature and pressure :
Find the number of moles of hydrogen present.

Explanation

To find the number of moles of hydrogen present in a gas cylinder that holds 1 kg of hydrogen, we can follow these steps:

### Step-by-Step Solution:

1. **Convert the mass of hydrogen from kilograms to grams**:
\[ \text{Mass of hydrogen} = 1 \text{ kg} = 1000 \text{ grams} \]
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