Question

calculate the mass of the non - volatile solute (molar mass =40g/mol-1) which should be dissolve in 114g octane to reduce it vapour pressure to 80%​

Answer 1

Answer:

Step-by-step explanation:

So, mole fraction of solute is $\dfrac{0.025x}{1+0.025x}$ . Now, the vapour pressure is to be lowered by 20%. We can see from the above calculation that the mass of a non-volatile solute that should be dissolved in 114g of octane to lower its vapour pressure by 20% is 10g.