When 0.5mol of a certain ionic substance is dissolved in 1.0kg of water, the freezing point of the resulting solution is -3.72 ∘ C .(Freezing point depression of water is -1.86 kgwater molsoluteparticles ). How many ions does the substance give when it dissolves?

Question

When 0.5mol  of a certain ionic substance is dissolved in 1.0kg  of water, the freezing point of the resulting solution is -3.72 ∘ C .(Freezing point depression of water is -1.86 kgwater molsoluteparticles   ). How many ions does the substance give when it dissolves?