Science

Experiment 1
Investigating the Effects of Temperature on Reaction Rate

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

Equipment:

• Conical Flask
• Beaker
• Measuring Cylinder
• Stopwatch
• Black cross on paper 
• Water Bath 
• Thermometer
• 0.1mol/L sodium thiosulfate 
• 1.0mol/L hydrochloric acid ( HCL ) 

Method: 

1. Put X on paper on the bench mat and put the conical flask on top of paper.
2. Measure 50 ml of sodium thiosulfate solution and put it into beaker. 
3. Record the temperature of the sodium thiosulfate.
4. Measure 5 ml of HCL and pour this into the conical flask. 
5. Pour the 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 from the mouth of the conical flask.
6. Wash flask thoroughly.
7. Repeat the experiment using a water bath to heat the sodium thiosulfate to 30 degrees 40 degrees and 50 degrees keep the volume of acid the same each time

Results 
room temp 28 seconds 

• 30 degrees 50 seconds 
• 40 degrees 19 seconds 
• 50 degrees 18 seconds 

Conclusion- A chemical reaction is when two or more particles collide with sufficient energy and at the correct orientation/angle. The faster the reactants move the higher chance of a successfulreaction to occur in a lesser time. 







Experiment 2  Investigating the effect of concentration on reaction rate

Aim: I want to investigate what impact concentration has on the reaction rate.

Equipment: 

• A conical flask 
• measuring cylinder 
• stopwatch
• black cross on paper 
• 0.2mol/l sodium thiosulfate 
• 1.0mol/l of hydrochloric acid 

Method: Put the piece of paper with the X on the bench and put the conical flask on it.

1. Measure 10mL of Sodium Thiosulfate and put it into the conical flask.
2. Measure 40mL of Water and put it into the conical flask. Swirl to mix.
3. Measure 5mL of HCl.
4. Pour the Sodium Thiosulfate into the conical flask, start the timer and swirl the flask.
5. Stop timing when the you can't see the cross on the paper.
6. Wash out the flask thoroughly.
7. Repeat experiment 20mL of Sodium Thiosulfate and 30mL of Water.
8. Repeat experiment 30mL of Sodium Thiosulfate and 20mL of Water.
9. Repeat experiment 40mL of Sodium Thiosulfate and 10mL of Water.
10. Repeat experiment 50mL of Sodium Thiosulfate and no Water.

Results 

10ml of thiosulfate and 40ml of water took 3:22 seconds to react
20ml of thiosulfate and 30ml of water took 1:58 seconds to react
30ml of thiosulfate and 20ml of water took 0:57 seconds to react
40ml of thiosulfate and 10ml of water took 0:52 seconds to react