Applications of Rate of Reaction

Keeping food in a refrigerator If food is kept in the fridge, the food will keep longer because the low temperature will slow down the rate of the chemical reaction which destroys food. Cooking food in a pressure cooker In a pressure cooker, the high pressure causes the water in the cooker to boil at … Read more

Collision Theory

The collision theory states that: The particles of the reacting need to touch to enable formation or breaking of the bonds for a reaction to happen. Collisions of particles of a reacting substance need to achieve a certain minimum energy (Activation Energy) in order to produce a reaction. Particles that collide also need to have … Read more

Pressure of Gas

Pressure of Gas For reactions involve gas, the rate of reaction is affected by the pressure of the gas. Pressure DOES NOT affect the rate of reaction where the reactants are in the form of solids or liquids. The higher the pressure of the gas, the higher the rate of reaction

Presence of Catalyst

Presence of Catalyst A catalyst is a substance which can change the rate of reaction. There are 2 types of catalyst: Positive catalyst – Increase the rate of reaction. Negative catalyst – Reduce the rate of reaction. Experiment 1 Set 1: Zinc + Hydrochloric AcidSet 2: Zinc + Hydrochloric Acid + Copper Sulphate (Catalyst) Chemical … Read more

Temperature of the Reactant

Temperature of the Reactant The higher the temperature of the solution, the higher the rate of reaction. Experiment By measuring the time taken for the formation of sulphur precipitate (yellow solid) when sulphuric acid, H2SO4 reacts with sodium thiosulphate(VI), Na2S2O3 of different temperature, we can investigate the effect of temperature of the reactant on the … Read more

Concentration of Reactants

Concentration of Reactants The higher the concentration of the solution, the higher the rate of reaction. Experiment By measuring the time taken for the formation of sulphur precipitate (yellow solid) when sulphuric acid, H2SO4 reacts with sodium thiosulphate(VI), Na2S2O3 of different concentration , we can investigate the effect of concentration of the reactant on the … Read more

Total Surface Area

Total Surface Area For reaction involves solid reactant, when the solid reactants is broken up into smaller pieces, the total surface area of the reactant become bigger. The bigger the total surface area of the reactant, the higher the rate of reaction. The smaller the size of the particle, the bigger the total surface area.  … Read more

Factors Affecting the Rate of Reaction

There are 4 factors that can affect the rate of a reaction, namely the total surface area of the reactant (solid only) the concentration of the reactant (solution only) the temperature of the reactant presense of catalyst in the reactant the pressure of the reactant (gas only) Total Surface Area For same amount of reactant, particles … Read more

Instantaneous Rate of Reaction from a Graph

Finding Instantaneous Rate of Reaction from a Graph The rate of reaction changes from time to time as the reaction happens. The rate of reaction at a particular time is called the instantaneous rate. The instantaneous rate of a reaction is equal to the gradient of tangent at a particular time. Rate of reaction = Δ(product) Δ(Time) Δ(Product) = Change of the amount of product … Read more

Average Rate of Reaction from a Graph

Finding the Average Rate of Reaction from a Graph Example In a reaction between calcium carbonate and liquid hydrochloric acid, carbon dioxide gas that is released is collected in a burette. The graph shows the volume of carbon dioxide collected over time. Find the average rate of reaction in the first 60s.Answer: