PLEASE HELP ME Calculate the change in boiling point when 0.402 moles of sodium chloride are added to 0.200 kilograms of water. Kf = -1.86°C/m; Kb = 0.512°C/m -2.1°C 2.1°C -7.5°C 7.5°C

The change in the boiling point would be 2.1°C.

Explanation:

1 ) Let us first determine the molarity of this solution :

M = mol / kg,

M = 0.402 mol / 0.200 kg = 2.01 M NaCl

2 ) ΔT = i K m

ΔT = 2 0.512C/m 2.01m

ΔT = 2.06C

As you can see, this is none of the answer choices. However the van't Hoff factor i in this case was taken to be 2, but this value is actually less than the predicted ideal solution. This is due to the ion pairing, causing i to be around 1.7 to 1.8. Therefore our solution is option b, 2.1°C.

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

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