Rates of Reaction

Question	Answer
What is the Reaction Time?	The time taken between a reaction starting and stopping.
What is a Reactant?	A substance that takes part in a chemical reaction. Reactants are written on the left hand side of a chemical equation.
What is Excess Reactant?	A reactant that is not all used up in a reaction that uses all of another reactant is said to be in excess.
What is Limiting Reactant?	Reactant that is completely used up in a reaction and so determines how much product can be made.
What is the rate of reaction controlled by?	The number of effective collisions occurring per second
Explain what increasing the concentration of reactants does.	More particles in the same volume will bump into each other more often.
Explain what increasing the temperature does.	The particles move more quickly, which means they collide more often. They also collide with more energy.
Explain what increasing the surface area does.	It allows more surface to come into contact with the other reactants.
How does a catalyst help speed up a reaction?	It provides an alternative route for the reaction to occur by.
Rate	Amount of change in the dependent variable/time measured for
What is a catalyst?	A catalyst increases the speed of a reaction, without being chemically changed or used up in the reaction.

Resource summary

	Created by Evie Papanicola about 11 years ago