Liquid and Gas
This is about Liquid and Gas Characteristics, Comparison between both fluids.
What is Liquid?
Liquid is a fluid which of its container. Other words, liquid possess definite mass and volume without definite shape.
Characteristics of gas:
- A given liquid mass occupies a fixed volume, irrespective of size & shape of container.
- Since assumption of liquid to be in-compressible, it will form a free surface if the container volume is greater than liquid as shown in figure.
- In liquids, the spacing between molecules is relatively higher as compared to solids, that means that inter-molecular cohesive forces are smaller in liquids. This allows liquid molecules to move freely within liquid mass.
- For liquids at narrow pressure above zero, depends on temperature.

Gas
What is gas?
Gas is a fluid which is definite mass but no definite volume and shape.
Characteristics of gas:
- A gas is relatively easily compressed and it is regarded as a compressible fluid.
- A mass of gas given has no fixed volume and It will expanding continuously unless restrained by a containing vessel.
- The spacing between molecules is extremely larger when compared to solids and liquids, that means inter-molecular cohesive forces is smaller in gases. So molecules of gas having greater free of moment. They will container completely in which they are placed.
- The volume of gas is depends on pressure and temperature. For instance, If the gas volume decreases then temperature and pressure of it increases.
Comparison between liquid and gas
SI.NO | Liquid | Gas |
1 | Possess a definite volume for a given mass of liquid, but conforms to shape of container. | It having a definite mass, but it does not posses a definite volume and conforms to shape of the container. |
2 | Since it posses a definite volume, it forms a free surface if the volume of container is greater than volume of liquid filled. | Since it does not have possess the definite volume, it will be expands and occupies the whole volume of container. |
3 | Fluid is incompressible | Fluid is compressible |
4 | The spacing between molecules is extremely larger when it compared to solids, but it relatively very less when it compared to gas. | The spacing between molecules is relatively larger when it compared to solids and liquids. |
5 | It can be contain in open vessel | It always needed to contain in a closed vessel. |