Vapour Pressure Is Independent

Vapour pressure is when the charged molecules are trying to enter the gaseous phase to free themselves. This means when there is liquid stored in an open or closed container when the liquid is in high amount or low and when the surface cover is large or small it doesn’t require any support and the liquid will be having vapour pressure independent of surface area. But there are some reasons why you can say that this theory is not true. Yes, liquid can be of anything but most of the time people take water into consideration which is understood because this is the only thing we see daily.

Better Understanding of vapour pressure dependency

Vapour pressure is known as pressure that is exerted by the liquid as per the atmosphere. Vapour pressure-totally depends on the type of liquid or liquid’s nature and temperature. When the vapour pressure is built when the liquid is present on the surface at that time vapour pressure is independent of surface area but they do need the surface to form vapour pressure. Even the small surface area can have vapour pressure built-in but vapour pressure doesn’t need much of surface area to reach the state of thermodynamic equilibrium.

When the liquid pressure is matching with atmospheric pressure at that time you will see not much vapour pressure building up. But when there is a change in atmosphere the liquid will start to show a different result, remember during this time too vapour pressure is independent of surface area. If you look at the methyl chloride it is having a high vapour pressure as compared to any other liquids. So if you see methyl chloride it will have to match the atmosphere to keep its pressure constant so you need to keep the boiling point at -24.2 °C.

Vapour Pressure according to the temperature

The vapor pressure depends on the temperature only and there is nothing else on which vapour pressure is dependent. There is complete vapour pressure independent of surface area and quantity. You can say many litres but still, the temperature will stay the same from the top of the liquid to the bottom of the liquid. If you are trying to give extra temperature you will be able to see vapour pressure moving more quickly but in a constant equilibrium state, there will not be much of change instead the natural energy will produce vapour pressure to enter the gaseous phase.

If you are thinking that vapour pressure independent of temperature then you may go wrong here because the energy is produced through the atmosphere and the atmosphere always has some temperature to connect the medium with others this is why if you try to lower the temperature you may see the molecules are not moving and they are stopped or stuck but there is still the evidence of vapour pressure.

Live example

You may have seen in ice that there are lines, those lines are of molecules trying to enter the gaseous phase to evaporate but they are stuck within the liquid. Here in this condition vapour pressure is independent of surface area because all the cooling temperature the liquid has received is on the outer layer first then it enters the mid-space where the vapor pressure depends on temperature which is stopping them to move faster.

If you are thinking that you can put them in a tight container then it may stop them from moving but you are wrong because the temperature on which the vapor pressure depend is already getting the energy it is just that you will see liquid will touch other parts of the surface but still vapour pressure independent of surface area because of one reason that gaseous phase which is taken by the vapour is struck between the container.

We have already seen when you boil water and store it in a tight container and then you try to open it which may ask you to put extra effort to open it then it means that energy force is trying to go out from that container. And if the container is going back to the normal temperature phase at that time you will see there is not much force involved to open the container as well.

Conclusion

We have observed in this article that the only thing that we disagree upon is vapour pressure independent of temperature otherwise all vapour pressure is totally independent of surface area, quantity, container etc. The earth’s atmosphere is always filled with energy and this is why you will see liquids fade off after some time as well but it doesn’t mean that will run away anywhere they all require energy to evaporate and enter gaseous form to reach equilibrium. The surface is long or short; there will be complete independence for any liquid.