The aim of this investigation is to look at the effect of varying concentration on the reaction between Zinc and Hydrochloric Acid.

* From recent knowledge I know that there are several main factors that affect the rate of reaction which include:

* The surface area of the reactants

* The concentration of the reactants

* The temperature at which the reaction is carried out.

For the surface area of the reactants I know that the rate of reaction is increased when the surface area is increased. This will have to be taken into account for a fair test.

I know that the rate of reaction increases when the temperature of the reaction is increased.

* As I am using the effect of varying concentration for the rate of reaction I will explain the collision theory, in effect of concentration. The collision theory supports the fact that reactions occur when particles collide with each other. This can be supported by the results of the experiment on the effect of concentration on reaction rates. This means that when solutions are more concentrated, the speed of a reaction is faster; A more concentrated solution means that there are more reactant particles in a given volume, meaning collisions will occur more often. The more often they collide, the more chance particles have of reacting, proving that the rate of chemical reaction will increase if the concentration of the reactants is increased. As this affects the rate of reaction, the concentration will need to be controlled to conduct a fair test.

The collision theory can be used to explain how concentration can affect the rate of reaction.

Concentration of acid

Low High

More chance of particles colliding

Help (ask Joelle): The acid is measured into the conical flask and the cylinder is filled with water from the trough. As the cylinder is turned upside down, so long as its mouth is kept under the water, the water will not fall out. The zinc is then added to the conical flask and the bung is replaced. I then start the stopwatch.

Apparatus:

The apparatus I will need for the experiment is the following:

* 2-3 decimal place balance

* Conical flask

* Timer

* Measuring cylinder

* Test tube

* Large beaker

* Bung

Safety Procedures:

For the experiment the following safety measures will be taken into account:

* I will wear a laboratory coat incase any hydrochloric acid escapes and gets onto my clothes.

* I will have to wear safety goggles due to the explosive nature of Hydrogen gas and also to protect my eyes from any other unsafe chemical.

Prediction:

I believe that as the concentration of the acid increases that the rate of reaction will increase, because a higher concentration in acid means that there is a larger amount of molecules in the solution that are reacting with the Zinc.

Results of the Experiment:

3 mol:

Minutes

Amount of Hydrogen

0

0

2

5

3

4

31

5

6

47

7

8

57

9

0

65

4mol:

Minutes

Amount of Gas

0

0

2

9

3

4

6

5

6

24

7

8

30

9

0

36

Minutes

Amount of Gas

0

0

2

3

4

6

5

6

24

7

8

30

9

0

36