Heat of Combustion

Question 1
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Pass Ratio : 100%
What is the heating value of 10 Kg of coal with heat of combustion 10 J/Kg?
-10 J
10 J
-100 J
100 J
Explanation:
Heating value = – Heat of combustion = -10*10 = -100 J.
Question 2
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What is the heat of reaction if the heat of combustion of products is 25 J and heat of combustion of reactants is 15 J?
-5 J
5 J
-10 J
10 J
Explanation:
Heat of reaction = 15 – 25 = -10 J.
Question 3
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What is the difference between higher heating value and lower heating value if the product has 5 moles of H2O and Enthalpy of vaporization is 10 J/mole at standard conditions?
10 J
-10 J
50 J
-50 J
Explanation:
HHV – LHV = 5*10 = 50 J.
Question 4
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What is the heat of reaction if the heat of combustion of products is 10 J and heat of combustion of reactants is 5 J?
-5 J
5 J
10 J
Cannot be determined
Explanation:
Heat of reaction = 5 – 10 = -5 J.
Question 5
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Pass Ratio : 100%
What is the heat of reaction if the heat of combustion of products is 10 J and heat of combustion of reactants is 15 J?
-5 J
5 J
10 J
Cannot say
Explanation:
Heat of reaction = 15 – 10 = 5 J.
Question 6
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Pass Ratio : 100%
What is the heat of reaction if the heat of combustion of products is 40 J and heat of combustion of reactants is 25 J?
5 J
10 J
15 J
-15 J
Explanation:
Heat of reaction = 25 – 40 = -15 J.
Question 7
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What is the value of higher heating value if the value of lower heating value is 10 J and the product has 5 moles of H2O and Enthalpy of vaporization is 4 J/mole at standard conditions?
10 J
20 J
30 J
40 J
Explanation:
HHV = 10 + 5*4 = 30 J.
Question 8
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What is the heating value of 2 Kg of coal with heat of combustion 15 J/Kg?
-15 J
15 J
-30 J
30 J
Explanation:
Heating value = – Heat of combustion = -15*2 = -30 J.
Question 9
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What is the difference between lower heating value and higher heating value if the product has 2 moles of H2O and Enthalpy of vaporization is 40 J/mole at standard conditions?
-40 J
40 J
-80 J
80 J
Explanation:
LHV – HHV = -2*40 = -80 J.
Question 10
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Pass Ratio : 100%
What is the heat of reaction if the heat of combustion of products is 2 J and heat of combustion of reactants is 10 J?
8 J
-8 J
4 J
-4 J
Explanation:
Heat of reaction = 10 – 2 = 8 J.