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NEET Questions / Chemistry / General Principles And Processes Of Isolation Of Elements / Ellingham Diagram
Consider the Ellingham diagram. Which metal oxide among the following can be reduced by coke at a temperature of 1500 K but not at 1200 K?
MgO
AlโOโ
ZnO
FeO
The Ellingham diagram for the formation of metal oxides shows a sudden increase in the slope for some metals. This is primarily due to:
Melting of the metal
Boiling of the metal
Phase transition of the metal
Formation of a non-stoichiometric oxide
Which of the following statements is INCORRECT regarding the Ellingham diagram?
The Ellingham diagram plots Gibbs free energy change as a function of temperature.
The Ellingham diagram assumes all reactants and products are in their standard states.
The Ellingham diagram can be used to determine the rate of a reaction.
The slope of the lines in the Ellingham diagram is determined by the entropy change of the reaction.
Why does the vs. T curve for the formation of from have a negative slope in the Ellingham diagram?
Increase in entropy due to increase in gaseous moles.
Decrease in entropy due to decrease in gaseous moles.
Constant entropy as gaseous moles remain the same.
The reaction is exothermic.
Given the Ellingham diagram, predict the minimum temperature at which magnesium can reduce to Si.
1500 K
1850 K
2000 K
2200 K
The Ellingham diagram does NOT directly account for which of the following factors that can influence the feasibility of a reduction reaction?
Temperature
Partial pressure of gases involved
Kinetics of the reaction
Entropy change of the reaction
Which of the following statements is true regarding the Ellingham diagram?
It shows the temperature dependence of the standard Gibbs free energy change for the formation of metal oxides.
It shows the pressure dependence of the standard Gibbs free energy change for the formation of metal oxides.
It shows the concentration dependence of the standard Gibbs free energy change for the formation of metal oxides.
It shows the entropy change for the formation of metal oxides.
In an Ellingham diagram, a reaction with a negative slope indicates:
The reaction becomes more spontaneous at higher temperatures.
The reaction becomes less spontaneous at higher temperatures.
The reaction is independent of temperature.
The entropy change is zero.
Ellingham diagrams are particularly useful for understanding the:
Reduction of metal oxides.
Oxidation of metals.
Neutralization reactions.
Solubility of salts.
What does a line with a positive slope on an Ellingham diagram represent?
An increase in entropy
A decrease in entropy
An increase in enthalpy
A decrease in enthalpy
