Rate of Reaction Strand I

When looking at my data and comparing my results from each catalyst I have come to the conclusion that Cobalt Chloride (CoCL2), was the catalyst that sped up the reaction to a greater extent than any other catalyst. The displacement of the hydrogen gas in the burette, in this experiment, was 15 seconds faster than the second quickest catalyst Nickel Sulphate. It was also a whole 50 seconds faster than the third fastest catalyst Copper Sulphate). The gradients on my graph also show that Cobalt chloride has a faster rate of reaction. The gradient calculations of the lines also show that CoCl2 was the catalyst that sped up the reaction the fastest at 3.5cm3/s compared to Nickel Sulphate 3.33333cm3/s. A steeper line and a larger gradient mean a faster rate of reaction.

According to collision theory, when molecules collide, bond formation and bond breakage occur creating new molecules. In this situation the particles were moving more quickly which increased the likelihood of productive collisions between CoCl2 and HCl or Zn, this also decreases the probability of non productive collisions between these particles. Comparing this reaction with zinc sulphate, I can see that this catalyst was ineffective because the catalyst did not speed up the chemical reaction. The catalyst had little effect in increasing the chance on productive collisions taking place as it had little effect on the pace of the experiment, and the reaction between the catalyst and Zinc was not very strong. This collision theory supports why the entire constant had to be kept the same. For example, if the temperature of the room was not the same then the HCl particles would have either and increased or decreased amount of Kinetic energy. This would affect the energy that the HCl particles had when they collided with the Zinc. If the temperature increased so would the rate of reaction because the HCl would have more kinetic energy and so the likelihood of productive collisions at activation energy with the Zinc increase.

Due to the fact of Copper sulphate being a known catalyst, I predicted that it would be the best catalyst because in my pilot tests is had shown to be very effective and so I did not think it could be beaten. The copper sulphate was effective in the experiment, bringing the H2 displacement to completion in an average of 105 seconds. My prediction on the worst catalyst was correct. I thought Sodium sulphate would be the worst because it is an alkali metal and they are known for not being very good catalysts. Overall I used and educated estimation to reach accurate predictions of the outcome of my prediction.

Catalysts are usually specific to a reaction and so they only work best at certain reactions. In this case Zinc Sulphate was not specific to the reaction and was useful. It only sped the reaction up by 0.1cm3/s compared to the non-catalyst experiment.

Zn-Zn/ HCl-HCl/Zn-H2/H20-H20

Activation