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3 years ago

Which solute would be more effective at lowering the freezing point of water: MgCl2 and KNO3? Explain.

Chemistry

2 answers:

Crazy boy [7]3 years ago

6 0

MgC12 because it’s colder then anything else

Phantasy [73]3 years ago

4 0

Answer:

AlCl₃.

Explanation:

Adding solute to water causes depression of the boiling point.

The depression in freezing point (ΔTf) can be calculated using the relation:

ΔTf = i.Kf.m,

where, ΔTf is the depression in freezing point.

i is the van 't Hoff factor.

van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass. For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.

Kf is the molal depression constant of water.

m is the molality of the solution (m = 1.0 m, for all solutions).

(1) NaCl:

i for NaCl = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

∴ ΔTb for (NaCl) = i.Kb.m = (2)(Kf)(1.0 m) = 2(Kf).

(2) MgCl₂:

i for MgCl₂ = no. of particles produced when the substance is dissolved/no. of original particle = 3/1 = 3.

∴ ΔTb for (MgCl₂) = i.Kb.m = (3)(Kf)(1.0 m) = 3(Kf).

(3) NaCl:

i for KBr = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

∴ ΔTb for (KBr) = i.Kb.m = (2)(Kf)(1.0 m) = 2(Kf).

(4) AlCl₃:

i for AlCl₃ = no. of particles produced when the substance is dissolved/no. of original particle = 4/1 = 4.

∴ ΔTb for (CoCl₃) = i.Kb.m = (4)(Kf)(1.0 m) = 4(Kf).

So, the ionic compound will lower the freezing point the most is: AlCl₃

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iren [92.7K]

Answer:

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3 years ago

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Tresset [83]

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3 years ago

Dehydrohalogenation of 1-chloro-1-methylcyclopropane affords two alkenes (A and B) as products.

UNO [17]

Explanation:

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3 years ago

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3 years ago

A cat travels 240 meters in 30 seconds, and a sprinter travels 100 meters in 9.5 seconds. Which is traveling faster, the cat or

joja [24]

Answer:

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Explanation:

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2 years ago