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प्रश्न
The pressure of a gas kept in an isothermal container is 200 kPa. If half the gas is removed from it, the pressure will be
विकल्प
100 kPa
200 kPa
400 kPa
800 kPa
उत्तर
100 kPa
Let the number of moles in the gas be n.
Applying equation of state, we get
\[PV = nRT\]
\[ \Rightarrow P = \frac{nRT}{V}\]
\[ \Rightarrow 2 \times {10}^5 = \frac{nRT}{V} . . . \left( 1 \right)\]
\[\text { When half of the gas is removed, number of moles left behind } = \frac{n}{2}\] \[\text { Let the pressure be P' }. \]
\[P' = \frac{n}{2}\frac{RT}{V}\]
\[\text { Now }, \]
\[P' = \frac{1}{2} \times 2 \times {10}^5 = {10}^5 \left[ \text { From eq } . \left( 1 \right) \right]\]
=100 kPa
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