| Describe ways to mesure rate of reaction. | 1)Mesuring mass change
-effective when carbon dioxide is produced as it leaves reaction container
-innefective for gases with small rfm like hydrogen
2)Mesuring volume change
-useful when gas leaves container
- mesured in gas syringe or burette or mesuring cylinder
3)Graph
-mass/volume of product on Y axis Time on X axis
-gradient equal to rate of reaction (steep gradient fast reaction) |
| How does an increase in concentration, pressure and surface area affect rate of reaction? | 1)reactant particles become more crowded
2)frequency of collisions between reactant particles increases
3)the rate of reaction increases
ENERGY DOESNT CHANGE |
| How does increased temperature affect rate of reaction? | 1)reactant particles move quicker
2)energy of particles increases
3)proportion of successful collisions increases
4)rate of reaction increases |
| What is a successful collision? | A colllision between reactant particles that has enough energy (activation energy or more) to produce a reaction |
| What is a catalyst how does it work? | a substance the changes the rate of reaction without being changed itself it finds an alternative reaction pathway that has a lower activation energy than the uncatalysed reaction thus increasing the frequency of successful colisions |
| Required practical to mesure the effect of concentration | 1)Support gas syringe with a stand, boss and a clamp
2)Add 50cm3 dilute hydrochloric acid to conical flask
3)Add 0.4g calcium carbonate to the flask attach the syringe and imediately start the stopwatch
4)Record gas collected every 10 seconds
5)Clean aparatus and reapat with different concentrations |
| Required practical to mesure temperature change? | 1)Add 50cm3 sodium thiosulphate soloutuion to conical flask
2)Mesure initial temperature
3)Place conical flask on paper with black cross
4)Add 10cm3 dilute hydrochloric acid to the conical flask start stopwatch
5)When black cross is no longer visible record the time on the stopwatch
6)Record temperature of reaction mixture
7)Clean aparatus and repeat with different temperatures of thiosulphate |
