H Chem - Controlling the Rate

Front

Why must reaction rates be controlled in industrial processes?

Back

If the rate is too low, the process will not be economically viable; if it is too high, there will be a risk of explosion.

Front

What can be used to explain the effects on reaction rates?

Back

Collision theory can be used to explain the effects of concentration, pressure, surface area (particle size), temperature, and collision geometry on reaction rates.

Front

What does a potential energy diagram show?

Back

A potential energy diagram shows the energy pathway for a reaction, including the enthalpy change and activation energy.

Front

What is enthalpy change?

Back

The enthalpy change is the energy difference between the products and the reactants. It is negative for exothermic reactions and positive for endothermic reactions.

Front

What is activation energy?

Back

Activation energy is the minimum energy required by colliding particles to form an activated complex. It can be calculated from potential energy diagrams.

Front

What is an activated complex?

Back

An activated complex is an unstable arrangement of atoms formed at the maximum of the potential energy barrier during a reaction.

Front

How does a catalyst affect a reaction?

Back

A catalyst provides an alternative reaction pathway with a lower activation energy, which can be shown on a potential energy diagram.

Front

What does temperature measure in a substance?

Back

Temperature is a measure of the average kinetic energy of the particles in a substance.

Front

What is the minimum kinetic energy required for a reaction to occur?

Back

The activation energy is the minimum kinetic energy required by colliding particles before a reaction may occur.

Front

How do energy distribution diagrams explain temperature effects?

Back

Energy distribution diagrams explain the effect of changing temperature on the kinetic energy of particles and reaction rate, including the effects of temperature and adding a catalyst.