NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Chemistry
- Chapter
- States of Matter
NTA Abhyas 2020 · Chemistry · States of Matter
At low pressure, the van der Waals' equation is reduced to
At low pressure, the van der Waals' equation is reduced to
Options
- A\text{Z}\text{=}\dfrac{{\text{PV}_{m}}{\text{RT}} \text{=}\text{1} - \dfrac{\text{aP}}{\text{RT}}
- B\text{Z}\text{=}\dfrac{{\text{PV}_{m}}{\text{RT}} \text{=}\text{1}\text{+}\dfrac{\text{bP}}{\text{RT}}
- C{\text{PV}_{m} \text{=}\text{RT}
- D\text{Z}\text{=}\dfrac{{\text{PV}_{m}}{\text{RT}} \text{=}\text{1} - \dfrac{a}{{V}_{m} \text{RT}}
Correct answer
D. \text{Z}\text{=}\dfrac{{\text{PV}_{m}}{\text{RT}} \text{=}\text{1} - \dfrac{a}{{V}_{m} \text{RT}}
Step-by-step solution
Van der Waals' equation (at low pressure),
at low pressure will be high
can be neglected \left(\text{P}\text{+}\dfrac{a}{{V}_m^{2}}\right){V}_{m} \text{=}\text{RT}{\text{PV}}_{m} \text{=}\text{RT} - \dfrac{a}{{V}_{m}}∴ \text{Z}\text{=}\dfrac{{\text{PV}}_{m}}{\text{RT}} \text{=}\text{1} - \dfrac{a}{{V}_{m} \text{RT}}
at low pressure will be high
can be neglected \left(\text{P}\text{+}\dfrac{a}{{V}_m^{2}}\right){V}_{m} \text{=}\text{RT}{\text{PV}}_{m} \text{=}\text{RT} - \dfrac{a}{{V}_{m}}∴ \text{Z}\text{=}\dfrac{{\text{PV}}_{m}}{\text{RT}} \text{=}\text{1} - \dfrac{a}{{V}_{m} \text{RT}}