(a) Differentiate between molarity and molality for a solution. How does a change in temperature influence their values? 

(b) Calculate the freezing point of an aqueous solution containing 10.50 g of MgBr₂in 200 g of water. (Molar mass of MgBr₂ = 184 g) (K_f for water = 1.86 K kg mol^-1) 

Molarity is defined as the number of moles of solute dissolved per liter of solution. 

 Molality of a solution is defined as the number of moles of solute dissolved in 1000 grams of solvent. 

While molarity decreases with an increase in temperature, molality is independent of temperature. This happens because molality involves mass, which does not change with a change in temperature, while molarity involves volume, which is temperature dependent.

b) Given 

 w₂ = 10.50 g 

w₁ = 200 g 

Molar mass of MgBr₂ (M₂) = 184 g 

 Using the formula,