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Data:
| Solution | BP(oC) | ΔBP(oC) | FP(oC) | ΔFP(oC) |
| H2O | 98.5 | XXXXX | 0 | XXXXX |
| C6H12O6 | 102.0 | 3.50 | -2.00 | 2.00 |
| KNO3 | 100.5 | 2.00 | -3.50 | 3.50 |
Analysis:
| Solution | avg Molality(m) | avg experimental molar mass(g/mol) | actual molar mass(g/mol) | avg percent error(%) |
| H2O | xxxxx | xxxxx | xxxxx | xxxxx |
| C6H12O6 | 3.94 | 107 | 180.156 | 40.6 |
| KNO3 | 1.45 | 104 | 101.11 | 2.97 |
KNO3:
Boiling:
m=2.00/(2*0.512)
m=1.94m *(50/1000)=0.097 mol
10/0.097= 103 g/mol
Freezing:
m=3.50/(2*1.85) =0.950m *(50/1000) =0.0475 mol
5/0.0475=105 g/mol
C6H12O6:
Boiling:
m=3.50/0.515 =6.80m *(50/1000)=0.34 mol
10/0.34=29.4 g/mol
Freezing:
m=2.00/1.85 = 1.08m 8(50/1000)=0.054 mol
10/0.054=185 g/mol
% error:
KNO3:
Boiling:
|103-101|/101 *100%=1.98% error
Freezing:
|105-101|/101 *100%=3.98% error
C6H12O6:
Boiling:
|29.4-180|/180 *100%=83.7% error
Freezing:
|185-180|/180 *100%=2.78% error