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Question
2 g of hydrogen is sealed in a vessel of volume 0.02 m3 and is maintained at 300 K. Calculate the pressure in the vessel.
Use R=8.3J K-1 mol-1
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Solution
Given:
Mass of hydrogen, m = 2 g
Volume of the vessel, V = 0.02 m3
Temperature in the vessel, T = 300 K
Molecular mass of the hydrogen, M = 2 u
No of moles, n =\[\frac{m}{M} = \frac{2}{2}\]= 1 mole
Rydberg's constant, R = 8.3 J/Kmol
From the ideal gas equation, we get
PV = nRT
\[\Rightarrow P = \frac{nRT}{V}\]
\[ \Rightarrow P = \frac{1 \times 8 . 3 \times 300}{0 . 02}\]
\[\Rightarrow\]P = 1.24 × 105 Pa
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