C5 Monitoring and Controlling Chemical Reactions Definitions:
Activation energy- the minimum amount of energy that particles must collide with to react.
Actual yield- the mass of product obtained from a reaction. It is normally less than the
theoretical yield due to incomplete reactions, side reactions and loss of product in transfer.
Atom economy- the measure of the amount of starting materials that end up as useful
products.
By-product- a secondary product made in the reaction of something else.
Catalyst- increases the rate of reaction by providing a different reaction pathway with a
lower activation energy. They are not used up during the reaction.
Closed system- a system in which nothing can get in and nothing can get out. A reversible
reaction will eventually reach equilibrium when carried out in a closed system.
Dynamic equilibrium- a reversible reaction will reach dynamic equilibrium when the rate of
the forward reaction is equal to the rate of the backward reaction. At dynamic equilibrium,
the concentration of reactants and products remains constant.
Enzymes- biological catalysts which speed up biochemical reactions so that organisms can
survive.
Le Chatelier’s principle- if a reaction at equilibrium is subjected to a change in
concentration, temperature or pressure, the position of equilibrium will move to counteract
the change.
Molar volume- the volume occupied by one mole of gaseous molecules.
Molar volume at RTP- the volume occupied by one mole of molecules of any gas at
room temperature and pressure (RTP). The molar volume at RTP is 24 dm 3 .
Percentage yield- the percentage ratio of the actual yield of product from a reaction
compared with the theoretical yield.
Rate of reaction- the measure of the amount of product formed or reactant used over time.
The units of rate of reaction may be given as g/s, cm 3 /s or mol/s.
Reaction profile- used to show the relative energies of reactants and products, the
activation energy and the overall energy change of a reaction.
Reversible reaction- a reaction in which the products can react together to reform the
reactants. Reversible reactions are denoted by the symbol ⇌.
Standard solution- a solution containing a known concentration of a substance.
Theoretical yield- the maximum possible mass of product that can be obtained from a
reaction.
Titration- a technique used where a solution of known concentration is used to determine
the concentration of an unknown solution.
Activation energy- the minimum amount of energy that particles must collide with to react.
Actual yield- the mass of product obtained from a reaction. It is normally less than the
theoretical yield due to incomplete reactions, side reactions and loss of product in transfer.
Atom economy- the measure of the amount of starting materials that end up as useful
products.
By-product- a secondary product made in the reaction of something else.
Catalyst- increases the rate of reaction by providing a different reaction pathway with a
lower activation energy. They are not used up during the reaction.
Closed system- a system in which nothing can get in and nothing can get out. A reversible
reaction will eventually reach equilibrium when carried out in a closed system.
Dynamic equilibrium- a reversible reaction will reach dynamic equilibrium when the rate of
the forward reaction is equal to the rate of the backward reaction. At dynamic equilibrium,
the concentration of reactants and products remains constant.
Enzymes- biological catalysts which speed up biochemical reactions so that organisms can
survive.
Le Chatelier’s principle- if a reaction at equilibrium is subjected to a change in
concentration, temperature or pressure, the position of equilibrium will move to counteract
the change.
Molar volume- the volume occupied by one mole of gaseous molecules.
Molar volume at RTP- the volume occupied by one mole of molecules of any gas at
room temperature and pressure (RTP). The molar volume at RTP is 24 dm 3 .
Percentage yield- the percentage ratio of the actual yield of product from a reaction
compared with the theoretical yield.
Rate of reaction- the measure of the amount of product formed or reactant used over time.
The units of rate of reaction may be given as g/s, cm 3 /s or mol/s.
Reaction profile- used to show the relative energies of reactants and products, the
activation energy and the overall energy change of a reaction.
Reversible reaction- a reaction in which the products can react together to reform the
reactants. Reversible reactions are denoted by the symbol ⇌.
Standard solution- a solution containing a known concentration of a substance.
Theoretical yield- the maximum possible mass of product that can be obtained from a
reaction.
Titration- a technique used where a solution of known concentration is used to determine
the concentration of an unknown solution.
