Solutions Test 8

Solutions that show a deviation from Raoult's law are called non-ideal solutions because they deviate from the expected behavior. Very few solutions actually approach ideality, but Raoult's law for the ideal solution is a good enough approximation for the non- ideal solutions.

The correct answer is option D
The solutions which obey Raoult's law over the entire range of concentration are known as ideal solutions.
For ideal solution, the enthalpy of mixing of the pure components to form the solution is zero and the volume of mixing is also zero, i.e.,
△_mix​H=0 and △_mix​V=0
Thus, this type of solution is a solution of benzene and toluene.

The correct option is B.

According to Raoult's law; the partial vapour pressure of each component of an ideal mixture of liquids is equal to the vapour pressure of the pure component multiplied by its mole fraction in the mixture
So for solvent
P = PA^oXA ; A→ solvent
P ∝ XA

The correct answer is option D
 
When a non - volatile solute is added into a volatile solvent to form an ideal solution. there will be a decrease in vapour pressure to that of solvent. According to roult's law the decrease in vapour is directly proportional to the mole fraction of solute in an ideal solution.
 

The correct answer is Option A.

(A – B) are stronger than the intermolecular interactions in A – A and B – B. 
For example, acetone and chloroform form a non-ideal solution showing negative deviation from Raoult's law. 
Volume of solution is less than the volume of solute and solvent.

The correct option C
The partial vapour pressure of each component of the solution is directly proportional to its mole fraction present in isolation.
Thus, for component 1
p₁ ∝ x₁ 
And  p₁ = p^о₁ x₁
Where p^о₁ is the vapour pressure of pure component 1 at the same temperature.
Similarly, for component 2
p₂ = p^о₂ x₂
Where p^о₂ represents the vapour pressure of the pure component 2.
According to Dalton’s law of partial pressure, the total pressure ptotal over the solution phase in the container will be the sum of the partial pressures of the components of the solution and is given as:
p_total =p₁ + p₂
Substituting the values of  p₁ and p₂, we get.
ptotal = x₁p₁⁰ + x₂p₂⁰
=(1-x₂)p₁⁰ + x₂p₂⁰
=p₁⁰  +(p₂⁰ - p₁⁰) x₂

The correct answer is option A
The vapor pressure of a solvent is lowered when a non-volatile solute is dissolved in it to form a solution. The vapor pressure lowering relative to pure solvent is , which is proportional to the mole fraction of solute.
 

Inter molecular interaction cause to evaporation. When inter molecular interaction high, their evaporation power decrease.

The correct answer is option D
chlorobenzene and bromobenzene
This mixture has two substances that only have dipole-dipole forces to exchange, and they therefore form essentially ideal solutions.