Question

As the number of solute particles in a solution increases, the effect on the freezing point of the solution increases. Which ionic compound will lower the freezing point the most if 1 mol of it is added to 1 L of water?

AlCl3


NaCl


KBr


MgCl2

Answer 1

AlCl₃

Step-by-step explanation:

Impurities depressing the freezing point of a solvent is called colligative property . It depends upon no of particles or ions of impurities. When the given compounds are dissolved in water , they break into ions and depress the freezing point . No of ions formed by one molecule of compound AlCl₃ on ionization is highest ( 4 ) . So this compound will have highest strength to lower the freezing point of solvent.

AlCl₃ = Al⁺⁺⁺ + 3Cl⁻

Total no of ions after ionization

= 1 + 3 = 4 .