General Principles And Processes Of Isolation Of Elements Class 12 Important Questions are very important for NEET, JEE as well as AIIMS exam. This is because it has many questions based on isolation of elements like hydrogen, chlorine, bromine and iodine from their respective mixtures. It tests your ability to isolate these elements through tests like vaporization, electrolysis and bulb method.
General Principles And Processes Of Isolation Of Elements Class 12 Important Questions (Thermodynamic Principles of Metallurgy)
1. How can a reaction with positive ΔG be made to occur?
a) By increasing the temperature
b) By decreasing the temperature
c) By coupling it with another reaction
d) It is not possible for the reaction to occur
Answer: By coupling it with another reaction
2. What does the Ellingham diagram consist of?
a) Plots of ΔfG° vs T
b) Plots of T vs ΔfG°
c) Plots of ΔfG° vs ΔS
d) Plots of ΔS vs ΔfG°
Answer: Plots of ΔfG° vs T
3. Under what condition can Al reduce MgO?
a) Above 1000°C
b) Below 1000°C
c) Above 1350°C
d) Below 1350°C
Answer: Above 1350°C
4. Which of the following is false regarding the Ellingham diagram?
a) It consists of plots of ΔfG° vs T
b) Ellingham diagrams are based on thermodynamic concepts
c) They do not tell us anything about the kinetics of the reduction process
d) They do not assume reactant-product equilibrium
Answer: They do not assume reactant-product equilibrium
5. Any metal will reduce the oxide of other metals which lie below it in the Ellingham diagram.
6. Which of the following statements is true?
a) Al can reduce ZnO more readily than Mg
b) Zn can reduce Cu2O more readily than Al
c) Mg can reduce ZnO more readily than Al
d) Zn can reduce Cu2O more readily than Mg
Answer: Mg can reduce ZnO more readily than Al
7. How are the oxides of less reactive metals like silver and mercury reduced?
a) By thermal decomposition
b) By electrolysis
c) By using reducing agents
d) Cannot be reduced
Answer: By thermal decomposition
8. Ellingham Diagram does not give any information regarding the kinetics of the reduction process.
9. Which of the following is the correct Gibbs equation?
a) ΔG = ΔH + TΔS
b) ΔG = ΔH – TΔS
c) ΔG = ΔH – 2TΔS
d) ΔG = ΔH – 3TΔS
Answer: ΔG = ΔH – TΔS
10. What is the criterion of the feasibility of a reaction at any temperature?
a) ΔG of the reaction must be positive
b) ΔG of the reaction must be negative
c) ΔG of the reaction must be equal to zero
d) Does not depend on ΔG of the reaction
Answer: ΔG of the reaction must be negative