EduNinjaSulfuric acid is manufactured by the Contact process.
One stage in this process is the conversion of sulfur dioxide into sulfur trioxide in the presence of a heterogeneous catalyst of vanadium(V) oxide, .
State the meaning of the term heterogeneous as applied to catalysts.
In the Haber process for the manufacture of ammonia, why is the heterogeneous catalyst iron in a finely divided state?
to increase its surface area
to produce the maximum reduction in the activation energy
to reduce its loss during the reaction
to reduce its surface area
Ammonia is manufactured by the Haber Process, in an exothermic reaction.
Assuming that the amount of catalyst remains constant, which change will not bring about an increase in the rate of the forward reaction?
decreasing the size of the catalyst pieces
increasing the pressure
increasing the temperature
removing the ammonia as it is formed
In the diagram, curve X was obtained by measuring the volume of oxygen produced during the decomposition of of hydrogen peroxide. A catalyst of manganese(IV) oxide was used.
Which alteration to the original experimental conditions would produce curve Y ?
adding more manganese(IV) oxide
adding some hydrogen peroxide
adding water
raising the temperature
Some oxides of elements in Period 3 are shown.
is an amphoteric oxide found in bauxite.
is used as a catalyst in the dehydration of alcohols.
State the effect of using as a catalyst in the dehydration of alcohols. Use the Boltzmann distribution in Fig. 2.1 to help explain your answer.
Fig. 2.1
Hydrogen peroxide decomposes slowly at to form water and oxygen.
The reaction is faster when a catalyst is present.
Which statement is correct?
The catalyst alters the Boltzmann distribution so that the reactant molecules have more energy.
The catalyst has no effect on the value of .
The catalyst increases the value of .
The catalyst provides a different reaction mechanism with a higher activation energy.
Nitrogen makes up about 79 % of the Earth's atmosphere. As a constituent element of proteins, it is present in living organisms.
Atmospheric nitrogen is used in the Haber process for the manufacture of ammonia.
What metal is most commonly used as the catalyst in a catalytic converter?
Construct one balanced equation for the reaction in which both CO and NO are removed from the exhaust gases by a catalytic converter.
Nitrogen makes up about 79 % of the Earth's atmosphere. As a constituent element of proteins, it is present in living organisms.
Atmospheric nitrogen is used in the Haber process for the manufacture of ammonia.
What metal is most commonly used as the catalyst in a catalytic converter?
Construct one balanced equation for the reaction in which both CO and NO are removed from the exhaust gases by a catalytic converter.
The diagram below shows, for a given temperature T, a Boltzmann distribution of the kinetic energy of the molecules of a mixture of two gases that will react together, such as nitrogen and hydrogen.
The activation energy for the reaction, , is marked.
On the energy axis of the graph opposite, mark the position, clearly labelled C, of the activation energy of the reaction when a catalyst is used.
Use your answer to (ii) to explain how the use of a catalyst results in reactions occurring at a faster rate.
Enzymes are biological catalysts. Many enzymes show specificity. An example of an enzyme which shows specificity is glucokinase. Glucokinase is involved in the metabolism of glucose.
What does specificity mean in this context?
Glucokinase is most effective as a catalyst over a narrow pH range.
Glucokinase is most effective as a catalyst over a narrow range of temperatures.
Glucokinase only operates on a narrow range of substrate molecules.
Glucokinase provides an alternative route for the reactions it catalyses.