Chemical Engineering

Merging Heat of Formation with Sensible Heat of Compound

Question 1
Marks : +2 | -2
Pass Ratio : 100%
What is the enthalpy of the reaction from 50oC to 52oC if CP = 15 J/oC, and the reference enthalpy is 25 J?
10 J
35 J
55 J
65 J
Explanation:
Enthalpy of reaction = 25 + 50∫5215.dT = 25 + 2*15 = 55 J.
Question 2
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What is the enthalpy of the reaction from 25oC to 40oC if CP = 10 J/oC, and the reference enthalpy is 10 J?
80 J
120 J
160 J
200 J
Explanation:
Enthalpy of reaction = 10 + 25∫4010.dT = 10 + 10*15 = 160 J.
Question 3
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What is the enthalpy of a reaction, if the standard heat of formation of a compound is 15 J and sensible heat of the compound is 25 J?
15 J
25 J
40 J
50 J
Explanation:
Enthalpy of reaction = 15 + 25 = 40 J.
Question 4
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What is the enthalpy of a reaction, if the standard heat of formation of a compound is 15 J, sensible heat of the compound is 25 J, and latent heat of the compound is 10 J?
25 J
40 J
50 J
65 J
Explanation:
Enthalpy of reaction = 15 + 25 + 10 = 50 J.
Question 5
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What is the enthalpy of the reaction from 10oC to 25oC if CP = 2 J/oC, and the reference enthalpy is 20 J?
50 J
60 J
75 J
90 J
Explanation:
Enthalpy of reaction = 20 + 10∫252.dT = 20 + 15*2 = 50 J.
Question 6
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What is the enthalpy of the reaction from 10oC to 15oC if CP = 5 J/oC, and the reference enthalpy is 25 J?
25 J
50 J
75 J
100 J
Explanation:
Enthalpy of reaction = 25 + 10∫155.dT = 25 + 5*5 = 50 J.
Question 7
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What is the enthalpy of a reaction, if the standard heat of formation of a compound is 10 J, sensible heat of the compound is 30 J, and latent heat of the compound is 20 J?
10 J
30 J
40 J
60 J
Explanation:
Enthalpy of reaction = 10 + 30 + 20 = 60 J.
Question 8
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What is the enthalpy of a reaction, if the standard heat of formation of a compound is 10 J and sensible heat of the compound is 5 J?
0
5 J
10 J
15 J
Explanation:
Enthalpy of reaction = 10 + 5 = 15 J.
Question 9
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How are enthalpies of streams calculated?
Relative to the reference state
Absolutely
Depends on the reaction
None of the mentioned
Explanation:
Enthalpies of the streams are calculated relative to the reference state.
Question 10
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Pass Ratio : 100%
What is the enthalpy of the reaction from 15oC to 25oC if CP = 3 J/oC, and the reference enthalpy is 15 J?
15 J
30 J
45 J
60 J
Explanation:
Enthalpy of reaction = 15 + 15∫253.dT = 15 + 3*10 = 45 J.