Effects of Concentration on the Rate of Reaction for Marble Chips and Hydrochloric Acid

Effects of Concentration on the Rate of Reaction for Marble Chips and Hydrochloric Acid

AIM

To investigate the effect of concentration on the rate of reaction for

marble chips and hydrochloric acid.

PRIOR KNOWLEDGE

A rate of reaction is the measurement of how quickly a product is

formed or how quickly a product is used up.

There are four things which affect the rate of reaction:

Ÿ Concentration

Ÿ Temperature

Ÿ Surface area

Ÿ Catalyst

Temperature - The temperature affects the rate of reaction because the

molecules have more energy so they move about more creating a faster

reaction. The higher the temperature the greater the activation speed

which makes more collisions, making the rate of reaction faster. For

any reactions to occur the particles need to collide.

Also the particles need energy to react otherwise they bounce off each

other. This will not give you a reaction. The energy you need to make

a reaction is called activation energy (Ea). The more you have, the

faster the reactions you will get.

Concentration - The concentration is how strong the acid is. The

stronger the acid is, the faster the reaction is, because the higher

the concentration the more particles there are which mean they are

more likely to collide. For any reaction that takes place particles

must collide. The way all rates of reaction are increased is by an

increase in the particles colliding with more energy. The acid

produces hydrogen irons (H+) which then react with CA CO3 (marble

chips). If you then triple it you are trebling the particles able to

react. If there are triple the collisions, this makes the rate of

reaction rise.

Catalyst - A catalyst is something which changes the speed of the rate

of reaction without being used, e.g. 2H2 O2 mno2 2H2O + O2

hydrogen water oxygen

peroxide

The rate of reaction is increased because the catalyst has a surface

for particles to hold on to.

Surface Area - The reaction happens faster when the solids are divided