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Question
1 mole of an ideal gas is contained in a cubical volume V, ABCDEFGH at 300 K (Figure). One face of the cube (EFGH) is made up of a material which totally absorbs any gas molecule incident on it. At any given time ______.
Options
the pressure on EFGH would be zero.
the pressure on all the faces will the equal.
the pressure of EFGH would be double the pressure on ABCD.
the pressure on EFGH would be half that on ABCD.
Solution
1 mole of an ideal gas is contained in a cubical volume V, ABCDEFGH at 300 K (Figure). One face of the cube (EFGH) is made up of a material which totally absorbs any gas molecule incident on it. At any given time the pressure on EFGH would be half that on ABCD.
Explanation:
The wall experienced pressure due to the force exerted by molecules on walls because of its rate of transfer of momentum to the wall. Due to elastic collision and magnitude of momentum transferred to the wall by each molecule is 2 mv but wall EFGH absorbs those molecules which strike on it. Therefore, the rate of change in momentum to it becomes only mv so the pressure of EFGH would be half of ABCD.
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