MCQ
Assertion $(A)$ : Gases do not liquefy above their critical temperature, even on applying high pressure.
Reason $(R)$ : Above critical temperature, the molecular speed is high and intermolecular attractions cannot hold the molecules together because they escape because of high speed.
  • $A$ and $R$ both are correct, and $R$ is the correct explanation of $A.$
  • B
    $A$ and $R$ both are correct, but $R$ is not the correct explanation of $A$.
  • C
    $A$ is true but $R$ is false.
  • D
    $A$ and $R$ both are false.

Answer

Correct option: A.
$A$ and $R$ both are correct, and $R$ is the correct explanation of $A.$
According to Andrews, a real gas cannot be liquefied ‘above critical ‘ temperature, whatever pressure is applied. Intermolecular force of gas molecules is low above critical temperature.

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