Energy Balances Application in Processes

Question 1
Marks : +2 | -2
Pass Ratio : 100%
What is the sensible heat of a reaction if the enthalpy of outputs is 5 J, and enthalpy of inputs is 10 J?
-5 J
5 J
-10 J
10 J
Explanation:
Q = ∆Houtput – ∆Hinput = 5 – 10 = -5J.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
What is the heat for the process for which theoretical flame temperature is defined?
Positive
Negative
Zero
Cannot say
Explanation:
Theoretical flame temperature is defined for adiabatic processes, => Q = 0.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
What is the heat of reaction if enthalpy of inputs and outputs at 25oC are 5 J and 8 J, the enthalpy of input and outputs at given temperature are 12 J and 15 J, enthalpy change of the reaction is 25 J?
20 J
25 J
30 J
35 J
Explanation:
Heat of reaction = (12 – 5) – (15 – 8) + 25 = 25 J.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
What is the sensible heat of a reaction if the enthalpy of outputs is 15 J, and enthalpy of inputs is 5 J?
3 J
5 J
10 J
15 J
Explanation:
Q = ∆Houtput – ∆Hinput = 15 – 5 = 10 J.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
If the temperature of the reaction is 25oC what will be the temperature of the products of the reaction for which theoretical flame temperature is defined?
25oC
45oC
75oC
100oC
Explanation:
For the reaction in which theoretical flame temperature is defined temperature of the products is same as the temperature of the reaction.
Question 6
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Pass Ratio : 100%
What are other effects occur in the process for which theoretical flame temperature is defined?
Electrical effects
Free radical formation
Ionization
No other effects
Explanation:
No other effect occurs in the process for which theoretical flame temperature is defined.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
How much the limiting reactant reacts in the process for which theoretical flame temperature is defined?
Completely
Partially
Does not react
None of the mentioned
Explanation:
The limiting reactant reacts completely in the process for which theoretical flame temperature is defined.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
What is the heat of reaction if enthalpy of inputs and outputs at 25oC are 10 J and 20 J, the enthalpy of input and outputs at given temperature are 25 J and 30 J, enthalpy change of the reaction is 50 J?
45 J
50 J
55 J
60 J
Explanation:
Heat of reaction = (25 – 10) – (30 – 20) + 50 = 55 J.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Theoretical flame temperature is defined for which process?
Isothermal
Adiabatic
Isobaric
Isochoric
Explanation:
Theoretical flame temperature is defined for adiabatic processes.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
What is the heat of reaction if enthalpy of inputs and outputs at 25oC are 10 J and 8 J, the enthalpy of input and outputs at given temperature are 5 J and 20 J, enthalpy change of the reaction is 30 J?
13 J
22 J
28 J
35 J
Explanation:
Heat of reaction = (5 – 10) – (20 – 8) + 30 = 13 J.