Multiple Choice Questions 10×1=10
1
What are the products of anaerobic respiration?
A
ATP + CO2 + H2O
B
CO2 + H2O
C
ATP + Ethanol + H2O
D
Ethanol + H2O
2
The word energy is used in physics for the first time:
A
1802
B
1805
C
1858
D
1902
3
The part of the universe that we want to focus our attention called:
A
System
B
Surrounding
C
Energy
D
Both A and B
4
What is the terms for the interface between a system and its surroundings?
A
System boundary
B
Surroundings boundary
C
Interface
D
All of the above
5
What is the unit of enthalpy?
A
Joules (J)
B
Calories (cal)
C
Kilojoules (kJ)
D
Kilocalories (kcal)
6
If ΔH° is positive, then reaction will be:
A
Exothermic
B
Endothermic
C
Both A and B
D
None of these
7
Bond dissociation for O2 is:
Hint: Bond dissociation energy is the energy required to break a chemical bond
A
498 KJ/mol
B
505 KJ/mol
C
605 KJ/mol
D
705 KJ/mol
8
Bond formation energy of one O-H bond is:
A
484 KJ/mol
B
486 KJ/mol
C
488 KJ/mol
D
None of these
9
What is the sign ΔH for an exothermic reaction?
A
Positive
B
Negative
C
Zero
D
Depends on the reaction
10
Which catalyst is used in promoting the breakdown of ozone?
A
Sodium
B
Gold
C
Silver
D
Chlorine
Short Answer Questions 15×2=30
1
What is the difference between enthalpy and enthalpy change?
ii
Why is breaking of a bond an endothermic process?
iii
Depict the transition state for the following reaction: H2 + Cl2 → 2HCl
H2 + Cl2 → 2HCl
iv
What is the role of glycogen in our body?
v
What is meant by chemical reaction?
vi
Who used the word energy?
vii
Why total enthalpy of system cannot be measured directly?
ix
How is enthalpy different from heat?
x
What is meant by exothermic reactions?
xi
Identify the following reaction, either it is endothermic or exothermic? C + O2 → CO2
Hint: Consider whether energy is released or absorbed in the reaction
xii
Can exothermic reaction be reversed?
xiii
What happens when two reactants molecules are mixed together?
xiv
Can energy be transferred in a form other than heat during a chemical reaction? Exercise
xv
Why it is not possible to calculate the enthalpy of a system? Exercise