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
Related Questions
The Ellingham diagram suggests that the reduction of alumina () by magnesium (Mg) is feasible. Which of the following statements best explains this feasibility?
The Gibbs free energy change for the overall reaction is positive.
The enthalpy change for the reaction is positive.
The entropy change for the reaction is negative.
The Gibbs free energy change for the overall reaction is negative.
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
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
In zone refining method, the molten zone :
contains impurities
contains purified metal only
contains more impurity than the original
moves to either side
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.
The Ellingham diagram for the formation of metal oxides shows a sudden change in slope for some metals. This is due to:
Phase transition of the metal.
Change in the oxidation state of the metal.
Formation of a non-stoichiometric oxide.
Change in the partial pressure of oxygen.
A sudden change in the slope of a line in an Ellingham diagram indicates:
A phase change in the metal or its oxide.
A change in the reaction mechanism.
A change in pressure.
A change in concentration.
In an Ellingham diagram, a line with a more negative slope than another indicates:
A larger increase in entropy during the reaction.
A smaller increase in entropy during the reaction.
A more negative enthalpy change for the reaction.
A less negative enthalpy change for the reaction.
In an Ellingham diagram, the slope of the line for the formation of a metal oxide is positive. This indicates that:
The entropy change for the reaction is negative.
The reaction becomes less spontaneous at higher temperatures.
The free energy change becomes more negative at higher temperatures.
The enthalpy change for the reaction is positive.
