Rates of Reaction

Experiment 1

Investigating the effect of temperature on reaction rate

Equipment

• A beaker, conical flask
• Measuring cylinder
• Stopwatch
• Black cross on paper
• water bath
• thermometer
• 0.1mol/L sodium thiosulfate
• 1.0 mol/L hydrocloric acid

Method

• Put the X paper on the bench mat,and put the conical flask on top of the paper
• Measure 50mL of sodium thiosulfate solution and put it in the beaker
• Record the temperature of the sodium thiosulfate
• Measure 5mL of HCL and pour into the conical flask 
• Pour the sodium thiosulfate into the conical flask, start the stopwatch and swirl the flask. Time how long it takes for the cross to disappear when viewed from above (i.e. look down the mouth of the conical flask)
• Wash out the flask thoroughly
• Repeat the experiment, using a water bath to heat the sodium thiosulfate to 30 degrees then 40 degrees and finally 50 degrees. Keep the volume of the acid the same each time 

Results
 Room temp  - 27sec
30 degrees - 8sec
40 degree - 7sec
50 degrees -5 sec

Conclusion:
A chemical reaction is when two reactant particles collide.
They must collide with enough force and in the correct orientation.
As I increased the temperature, the reactants gained more kinetic energy and moved faster.
The faster they move, the higher the chance of a successful collision.
This means the rate of reaction will increase.

Experiment 2
Investigating the effect of concentration effects the reaction rate

Aim:
I want to investigate how concentration effects the reaction rate.

Equipment

• Conical Flask
• Beaker
• Measuring Cylinder
• Stopwatch
• Waterbath
• Paper with a black cross "X"
• Thermometer
• 0.1mol/L Sodium Thiosulfate
• 2.0mol/L Hydrochloric Acid

Method

1. Put the piece of paper with the X on the bench and put the conical flask on it.
   
   
2. Measure 10mL of Sodium Thiosulfate and put it into the conical flask.
   
   
3. Measure 40mL of Water and put it into the conical flask. Swirl to mix.
4. Measure 5mL of HCl.
5. Pour the HCl into the conical flask, start the timer and swirl the flask.
6. Stop timing when the you can't see the cross on the paper.
   
   
7. Wash out the flask thoroughly.
8. Repeat experiment 20mL of Sodium Thiosulfate and 30mL of Water.
9. Repeat experiment 30mL of Sodium Thiosulfate and 20mL of Water.
10. Repeat experiment 40mL of Sodium Thiosulfate and 10mL of Water.
11. Repeat experiment 50mL of Sodium Thiosulfate and 0mL Water.

Results:

10mL Thiosulfate/40mL Water took 360sec for the X to disappear.
20mL Thiosulfate/30mL Water took 100sec for the X to disappear.
30mL Thiosulfate/20mL Water took 64sec for the X to disappear.
40mL Thiosulfate/10mL Water took 47sec for the X to disappear.
50mL Thiosulfate/0mL Water took 30sec for the X to disappear.

Experiment 3
Investigating the effect of surface area on reaction rate

Aim - I want to investigate how changing the surface area effects the reaction rate
Equipment:

• Boiling tube
• Calcium carbonate (marble chips)
• Calcium carbonate powder
• 1.0mol/L Hydrochloric acid
• Measuring cylinder
• Spatula
• Test tube tongs

Method: 

• Measure 2mL of hydrochloric acid and pour it into a boiling tube
• using the tongs to hold the boiling test tube over the sink, add a pea-sized amount of Calcium Carbonate powder.
• Repeat experiment instead using the same amount of marble chips rather than the powder

Results:

When I added the powder, there was vigorous fizzing.
When I repeated the experiment with the chips, it bubbled.

Conclusion:
A chemical reaction is when two reactant particles collide.
They must collide with enough force and in the correct orientation.
As I increased the surface area of the reactants, there were more reactant particles that were able to react. The more particles, the higher the chance of a successful collision.
This means the rate of reaction will increase.

Experiment 4
Investigating the effect of a catalyst on the reaction rate

Aim - I want to investigate how adding a catalyst will effect the reaction rate
Equipment

• Test tubes x 3
• Zinc metal granules
• Copper metal powder
• 1.0mol/L Hydrochloric acid
• Measuring cylinder
• Spatula

Method 

• Put a piece of zinc into test tube 1 and test tube 3
• Put a small amount of copper powder into test tube 2 and test tube 3
• Add 5mL of acid to each test tube

Results 

Test tube 3 bubbles and fizzed the most because the catalyst lowered the activation energy.

Conclusion:

A chemical reaction is when two reactant particles collide.
They must collide with enough force and in the correct orientation.
A catalyst is a chemical that itself is not used in the reaction, however it lowers the Activation Energy - the amount of energy required for a successful collision.
If less energy is needed, then more particles will have the required energy to react, therefore the reaction rate will increase