3.4 Rates of Reaction

-Collide -Have collision energy that is same as activation energy. -Collide with correct orientation.

-More reactant particles per unit volume. -This increases collision frequency . -% of successful collisions stays same. -Applies for gases only.

-More particles avaliable that have the potential to collide. -Speeds up the rate of the reaction. -Increases collision frequency.

-Particles have more KE and move faster. -Increases collision frequency. -Increases rate of reaction. -Increases % of collisions that have activation energy for collisions to happen.

-Lowers activation energy needed for a collision to occur. -Collision frequency stays same. -Increases % of collisions that cause a successful reaction.

-Speeds up rate of a reaction but doesn’t undergo any permanent change itself. -Provides and alternative reaction pathway by lowering activation energy needed for collisions to cause a reaction.

A catalyst that is in the same physical state as the reactants. Reacts with reactants to form intermediates. Eg., carboxylic acid +alcohol = ester +water

A catalyst in different physical state as the reactants. Usually solids that react with gaseous/ aqueous reactants.

Reactant molecules are absorbed on surface of catalyst. After, product molecules leave catalyst by de-absorption.

Must be fitted in petrol cars. Contain catalysts made of platinum, palladium and rhodium on a honeycomb mesh that provides a large SA.

The hot exhaust gases pass over heterogenous catalysts and harmful gases are converted into less harmful products that are safe to leave the engine.

90 %

If a chemical reaction uses less energy, then less fossil fuels or electricity is need to heat the reaction.

Makes more products faster and cuts costs to increase profitability. Economic advantages outweigh developing catalyst. There are higher atom economies and fewer pollutants.

The spread of molecular energies in gases, where you can see the activation energy. It concerns particles/ molecules of a gas, liquid or solution.

As there are no particles with no kinetic energy.

Area under the curve is equal to total number of molecules.

There is no value for maximum kinetic energy on x axis as curve never reached x axis.

The graph move to the right and down and there are more particles that have the kinetic energy same as the activation energy to cause a reaction.

The graph stays same but activation energy is lower. There is a greater number of molecules that have the amount of energy needed for a reaction.

Where forward and reverse reaction are ongoing.

-Rates of forward and reverse reactions are the same. -Net concentrations remain the same. -Must be a closed system.

Use 2 plastic straws and fill one cullender with water. Transfer water using straws, from one cylinder to the other until dynamic equilibria is reached.

When a system is in dynamic equilibrium, any change in external conditions will cause the equilibrium to adjust itself to oppose the change.