Question

2.0 g of H₂ gas is adsorbed on 2.5 g of platinum powder at 300 K and 1 bar pressure. The volume of the gas adsorbed per gram of the adsorbent is _____ mL.
(Given : R= 0.083 L bar K^–1 mol^–1)

Answer 1

Correct Answer: 9960

To find the volume of H₂ gas adsorbed per gram of platinum powder, we follow these steps:
1. **Determine the moles of H₂:**
Molar mass of H₂ = 2.0 g/mol
Moles of H₂ = 2.0 g / 2.0 g/mol = 1.0 mol
2. **Use the ideal gas law to find the volume at 1 bar and 300 K:**
The ideal gas law is given by:
\( PV = nRT \)
Where \( P = 1 \) bar, \( n = 1.0 \) mol, \( R = 0.083 \) L bar K^–1 mol^–1, and \( T = 300 \) K.
Substitute the values:
\( V = \frac{nRT}{P} = \frac{1.0 \times 0.083 \times 300}{1} = 24.9 \) L
3. **Convert the volume to mL:**
\( 24.9 \) L = \( 24900 \) mL
4. **Find the volume adsorbed per gram of adsorbent:**
Total volume adsorbed = 24900 mL
Mass of adsorbent (platinum) = 2.5 g
Volume adsorbed per gram = \( \frac{24900}{2.5} = 9960 \) mL/g
5. **Verify against the range:**
The computed value is 9960 mL/g, which fits within the range 9960 to 9960.
Result: The volume of the gas adsorbed per gram of platinum powder is 9960 mL.