Investigating Factors that Affect the Rate of Reaction

Investigating Factors that Affect the Rate of Reaction

1.0 Introduction

The rate of a reaction is a measure of how quickly reactants are used

up or products are made. There are many factors which will affect the

rate of reaction between 2 reactants. These are: surface area of the

potato chip, temperature of the liquid, catalyst, light, physical

stirring and concentration of liquid. In this experiment I shall look

at the effect of concentration on the rate of reaction between

hydrogen peroxide (H2O2) and a catalyst- catalase, which is found in

potato chips. Hydrogen peroxide is a toxic by product of metabolism.

Catalase is one of the fastest acting enzymes known. And when reacted

with hydrogen peroxide it catalases the decomposition of hydrogen

peroxide giving out oxygen

I shall start off with background theory and use it to make a

prediction and then plan and carry out a safe procedure to obtain

enough, reliable evidence to test my predictions. From my data I shall

plot graphs and I shall finish off by looking at errors and

inaccuracies in my procedure and suggest improvements.

2.0 Background Theory

Collision theory

The rate of a reaction simply depends in how often and how hard the

reacting particles react with each other. The basic idea is that the

particles have to collide in order to react.

If the reactant is a solid (i.e. potato) then breaking it up into

smaller pieces will increase its surface area, so the particles (H2O2

particles) around it will have more useful collisions which would

increase the rate of reaction. If the temperature is increased the

particles all move quicker (vibrate more). If they are moving quicker

they will have more collisions, speeding up the reaction. Catalysts

increases the speed of a reaction, they work by giving the reacting

particles a surface to stick to, where they can bump into each other,

which would increase the number of collisions. If a solution (H2O2) is

more concentrated it means there are more particles of reactant (H2O2