T6:The rate and extent of chemical change.

What is the equation linking the quantity of reactant used,mean rate of reaction and time taken?

What is the equation linking the quantity of product formed,mean rate of reaction and time taken?

How can the quantity of a reactant or product be measured by?

Mass in grams or by a volume in cm3.

What are the two units for the rate of a reaction?

g/s or cm3/s.

How does increasing the temperature increase the rate of reaction?

• When the temperature of the particles in increased

• they gain more kinetic energy

• so move faster

• so they collide more frequently

• Therefore,the faster they move,the more collision they have so more of the particles will have the activitation energy to amke the reaction happen.

How does increasing the concentration increase the rate of reaction?

• If the concentration is increased then there are more particles in the same volume

• meaning that there are more freuent collisions

• nand more collisions between particles with the activation energy

• means that it increases the rate of reaction

How does increasing the pressure increase the rate of reaction?

• Increasing the pressure

• means that there is less sapce between the particles

• so there are more frequent collisions between the particles

• leading to a higher probability of successful reactions

• increasing the rate of the reaction

How does increasing the surface area increase the rate of reaction?

• Increasing the surface area

• means tht for the same volume of solid

• the particles will have more area to work on

• so there wil be more frequent collisions

• increasing the rate of reaction

How does a catylst increase the rate of reaction?

• A catalyst increasing the arte of reaction

• by decreasing the activation energy needed for the reaction to occur

• which is done by the catalyst providing an

• alternate reaction pathway with a lower activation energy.

When is the only instance when chemical reactions can occur?

Chemical reactions can occur only when reacting particles collide with each other and with sufficient energy.

What is the activation energy?

The minimum amount of energy that particles must have to react.

What is a catalyst?

A catalyst is a substance that increases the rate of a reaction wihtout being used up in the reaction itself.

What do different reactions need?

Different catalysts.

What do enzymes act as in bioloicl systems?

Catalysts.

Draw a reaction profile for a catalysed reaction: