A gas absorbs 10J of heat and is simultaneously compressed by a const and external pressure
of 0.5 atm from 4L to 2L in volume What
is the change in the internal energy.
A. 101J b. 111J c.2J d. none of the above

Given :

Heat absorbs , Q = 10 J .

Pressure ,

Initial volume , .

Final volume , .

To Find :

The change in the internal energy .

Solution :

By first law of thermodynamics :

Here , W is work done ,

Therefore,

Putting values in SI units in above equation :

Therefore , option b. is correct .

Hence , this is the required solution .

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.