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A compound M X₂ separates into M²⁺ and X⁻ ions in water, with a dissociation extent (α) of 0.5. What is the ratio of the actual freezing point depression of the solution to the freezing point depression if no dissociation occurred?

1. 1
2. 2
3. 3
4. 4

Correct answer: 2

Solution

The correct answer is 2 because the dissociation extent of the compound affects the freezing point depression, and in this case, the actual freezing point depression is twice the value if no dissociation occurred, due to the increase in the number of particles in the solution.

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