Solutions

Given, density

Mass of solute

Molar mass of solute

Mass of solvent

Total mass



Total volume

Molarity

Molarity

Answer (b) 0.21

No. of moles of HCL= =0.5
Molality (m)=Mass of solvent in kg
No. of mass of solute​
Molality =5000.5×1000​=1m

The total pressure is given by Raoult's law: Where the individual pressures are calculated by: Substitute , so . The partial pressures are: Now calculate the mole fractions in vapour phase:

We are given the following information:
Vapour pressures of A and B at 300 K are 500 mm Hg and 400 mm Hg, respectively.
Equal moles of A and B are mixed to form an ideal solution. We are asked to find the mole fraction of A and B in the vapor phase. Step 1: Use Raoult's Law Raoult's Law states that the partial pressure of each component in the vapor phase is directly proportional to its mole fraction in the liquid phase: Where:
and are the partial pressures of A and B in the vapor phase,
and are the mole fractions of A and B in the liquid phase,
and are the vapor pressures of pure A and B at 300 K. Since equal moles of A and B are mixed, the mole fraction of A and B in the liquid phase is:
Step 2: Calculate the partial pressures of A and B in the vapor phase Using Raoult's Law, the partial pressures of A and B in the vapor phase are:
Step 3: Calculate the total pressure The total pressure of the system is the sum of the partial pressures of A and B:
Step 4: Calculate the mole fraction of A and B in the vapor phase The mole fraction of A and B in the vapor phase is given by: Thus, the mole fractions of A and B in the vapor phase are approximately 0.555 and 0.444, respectively.