Related Questions
The Ellingham diagram plots the change in which thermodynamic quantity against temperature?
Gibbs Free Energy
Enthalpy
Entropy
Internal Energy
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.
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.
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 method of purification is represented by the following equation:
Zone refining
Cupellation
Polling
Van Arkel
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.
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.
Considering Ellingham diagram, which of the following metals can be used to reduce alumina?
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.
