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20. Which of the following substances would you predict to have the highest AHvap?

A) CH3C1

B) HCI

C) HOCH₂CH₂OH

D) CH3CH2OH

E) CH3CH2CH2CH3

21. Calculate the mass of water (in g) that can be vaporized at its boiling point with 155 kJ of heat.

AHvap 40.7 kJ/mol (at 100 °C)

-

18.02 g H₂O- 1 mol H₂O

22. How much energy is required to heat 1.00 mole of ice from -25.0°C to 125.0 °C?

Temperature (°C)

ke warming

0.941 klimol

q=mxCAT

125

100-

75

50

25

0

-25-

Melting

point

0

ke melting to liquid

6.02 klimal

gom.x. Δεν

Boiling

point

10

Water

Liquid water warming

7.53 kmal

CAT

30

40

Heat added (kJ/mol)

Liquid water

waporting to steam

40.7 km

q=nx &Hu

50

Steam warming

0.905 kel

4-CAT

5

Vape

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