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soldi70 [24.7K]

3 years ago

7

When 1.0g of diethyl ether is converted to vapor at its boiling point, about how much heat is absorbed? (C4H10O, Hvap= 15.7kj/mo

l, boiling point:34.6°C)
A) 2 J
B) 2 kj
C) 0.2 J
D) 0.2 kj

(Please show how you got the answer.)

1 answer:

Aloiza [94]3 years ago

8 0

Answer:

Option D = 0.2 Kj

Explanation:

Given data:

Mass of diethyl ether = 1.0 g

Hvap = 15.7 Kj / mol

Heat absorbed = ?

Solution:

Q = mass × Hvap / molar mass

Q = 1.0 g × 15.7 Kj / mol / 74.12 g/mol

Q = 15.7 Kj / 74.12

Q = 0.212 KJ

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We just take the positive values from the solution since negative partial pressures don´t make physical sense.

Kp = 1.4

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We follow the same analysis for the other values of Kp.

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Not sense.

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