The Rate of a Chemical Reaction When Changing the Concentration of Hydrochloric Acid

The Rate of a Chemical Reaction When Changing the Concentration of Hydrochloric Acid

I am going to investigate the effect of the concentration of the acid

solution, Hydrochloric acid to see how this changes the rate of

reaction. For my experiment I will use sodium thiosulphate as my

constant and I will be changing the concentration of hydrochloric acid

and water.

I predict that as the concentration of hydrochloric acid increases,

the rate of reaction also increases. I also think that the time taken

for the experiment to finish will decrease as the concentration of the

hydrochloric acid will increase.

These graphs show my expected results:

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In a high concentration, there are more particles of hydrochloric acid

in a certain volume, this means there is a higher chance of a

collision because there are more acid particles. As there are more

collisions, the rate of reaction will increase.

The 'Colliosion Theory' supports my prediction as for a chemical

reaction to happen, the reacting particles must bang into, or collide,

with each other with enough force or energy ( the activation energy)

to break bonds. This is collision theory. If the particles do not have

have this energy, they will just harmlessly bounce off one another. If

two particles meet, they may rebound with no reaction, but if they

collide with enough force, a chemical reaction will occur. (The

Dorling Kindersley Science Encyclopedia)

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In the low concentrated solution, it shows there are less particles of

hydrochloric acid to collide with the sodium thiosulphate particles.

In the second box, the high concentrated solution there are more

particles of hydrochloric acid, so the chance of collision is

increased.

Method

I am aware that there are many safety precautions which I will have to

follow:

· Immediately wash hands and other parts of skin if incontact with

hydrochloric acid as it is an irritant and is harmful to skin and

eyes.

· Rinse out mixture in flask and leave water running to get rid of the