Answer:
[tex]\large \boxed{\text{-11.2 $^{\circ}$C}}[/tex]
Explanation:
The formula for the change in freezing point ΔT_f caused by an electrolyte is
[tex]\Delta T_{f} = -iK_{f}b[/tex]
1. Calculate i
Na₂SO₄(aq) ⟶ 2Na⁺(aq) + SO₄²⁻(aq)
1 mol Na₂SO₄ gives 3 mol ions.
i = 3
2. Calculate the freezing point
(a) Change in freezing point
[tex]\Delta T_{f} = -iK_{f}b = -3 \times 1.86 \times 2.00 = -11.2 \,^{\circ}\text{C}[/tex]
(b) Freezing point
[tex]\Delta T_{f} = T_{f} - T_{i}\\ T_{f} = \Delta T_{f} + T_{i} = 0.00 - 11.22 = \large \boxed{\textbf{-11.2 $^{\circ}$C }}[/tex]
