Chemistry

1. THE EFFECT OF TEMPERATURE CHANGES ON REACTION RATE

2. INTRODUCTION INITALLY THE REACTION MIXTURE IS PURPLE, BUT IT WILL TURN COLOURLESS. 5(COOH)2 + 6H + 2Mno4 2Mn2 + 10CO2 + 8H2O Oxalic acid reacts with acidified solution of potassium permanganate.

3. REQUIREMENTS 100 ml erlenmeyer 600 ml beaker Timer Heater Thermometer Deionised water 3 syringes gloves 0.2 M oxalic acid 1M sulphuric acid 0,02 M potassium permanganate

4. PROCEDURE Using syringes add: 5 cm3 of sulphuric acid, 2 cm3 of potassium permanganate solution 40cm3 of water to a 100cm3 dry erlenmeyer.

5. Heat the mixture to about 40ºC. Place the beaker on a white paper

6. Whenthe mixture isover40ºC, add1 ml of oxalicacidand removefromtheheat. Afterthereaction mixture turnscolourless, stop thetimer and record the time.

7. REPEAT THIS PROCEDURE THREE TIMES AT: 50ºC, 60ºC AND 70ºC.

8. TABLE

10. QUESTIONS State the aim of the experiment. - The aim of the experiment is to observe the effect of temperature changes on reaction rate

11. 2. Statetwofactorswhichhadtobekeptconstant in theexperiments - Twofactorswhichhadtobekeptconstantwerevolume and pressure.

12. How was the rate of the reaction determined? When we increase the temperature the reaction rate is very fast, but when we decrease the temperature the reaction rate is very slow.

13. SARA PÉREZ BONILLA AND IRENE MUÑOZ