Place the solutions below in order of increasing freezing point, and explain the
ID: 946050 • Letter: P
Question
Place the solutions below in order of increasing freezing point, and explain the order: .15 m (molality) CH3OH (methanol), .10 m NaCl (sodium chloride), .18 m CH3CH2OH (ethanol), .080 m Na2SO4 (sodium sulfate) Place the solutions below in order of increasing freezing point, and explain the order: .15 m (molality) CH3OH (methanol), .10 m NaCl (sodium chloride), .18 m CH3CH2OH (ethanol), .080 m Na2SO4 (sodium sulfate) .15 m (molality) CH3OH (methanol), .10 m NaCl (sodium chloride), .18 m CH3CH2OH (ethanol), .080 m Na2SO4 (sodium sulfate)Explanation / Answer
CH3OH does not dissociate into ions. so it is 0.15 m - highest freezing point
NaCl dissociates into two ions. so it is 0.10 * 2 = 0.2 m
CH3CH2OH does not dissociate. so it is 0.18 m
Na2SO4 dissociates into three ions. so it is 0.080 * 3 = 0.24 m - lowest freezing point
As the molality increases freezing point decreases, so
Na2SO4(0.24 m) < NaCl(0.2 m) < CH3CH2OH(0.18 m) < CH3OH(0.15 m)