MCQ
The quantity $\frac{\text{PV}}{\text{kT}}$ represents:
- AMass of the gas.
- BKinetic energy of the gas.
- CNumber of moles of the gas.
- ✓Number of molecules in the gas.
✓
Answer
Correct option: D.
Number of molecules in the gas.
Here,
$\text{PV = nRT ...(1)}$
Also,
$\text{k}=\frac{\text{R}}{\text{N}}$
$\Rightarrow\text{R}=\text{kN}\ ...(2)$
Now,
$\text{PV = nkNT} [$From eq. $(1)$ and eq. $(2)]$
$\Rightarrow\text{nN}=\frac{\text{PV}}{\text{kT}}$
$nN =$ Number of molecules
$\frac{\text{PV}}{\text{kT}} =$ Number of molecules.
$\text{PV = nRT ...(1)}$
Also,
$\text{k}=\frac{\text{R}}{\text{N}}$
$\Rightarrow\text{R}=\text{kN}\ ...(2)$
Now,
$\text{PV = nkNT} [$From eq. $(1)$ and eq. $(2)]$
$\Rightarrow\text{nN}=\frac{\text{PV}}{\text{kT}}$
$nN =$ Number of molecules
$\frac{\text{PV}}{\text{kT}} =$ Number of molecules.
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Choose the most appropriate answer from the options given below: