Negative deviation from Raoult's law occurs when the interactions between different molecules in a mixture are stronger than the interactions between the same types of molecules when they are pure. This leads to a decrease in vapor pressure compared to what is expected based on ideal behavior. In terms of the given options:
Thus, the mixture benzene-chloroform demonstrates negative deviation from Raoult's law due to strong intermolecular forces such as hydrogen bonding between different molecule types.
Raoult's law states that the partial vapor pressure of each volatile component in a solution is directly proportional to its mole fraction in the solution. In real solutions, deviations from Raoult's law are observed.
These deviations are classified into two types:
- Negative deviation: This occurs when the intermolecular forces between the solute and solvent molecules are stronger than those between the solvent molecules themselves. As a result, the vapor pressure of the solution is lower than predicted by Raoult's law.
- Positive deviation: This occurs when the intermolecular forces between the solute and solvent molecules are weaker than those between the solvent molecules themselves, leading to a higher vapor pressure than predicted by Raoult's law.
In the case of benzene-chloroform, the intermolecular forces between the benzene and chloroform molecules are stronger than those between benzene molecules, leading to a negative deviation from Raoult's law.
Thus, the correct answer is Benzene-chloroform.
A solid cylinder of mass 2 kg and radius 0.2 m is rotating about its own axis without friction with angular velocity 5 rad/s. A particle of mass 1 kg moving with a velocity of 5 m/s strikes the cylinder and sticks to it as shown in figure.
The angular velocity of the system after the particle sticks to it will be: