PAG 10.2 transition elements as catalysts

Question 1

method

Answer 1

1) weigh 2.5g of potassium sodium tartrate into a 400 cm3 beaker. add 30 cm3 of distilled water and stir to dissolve the solid
2) add 10 cm3 of 20 vol. hydrogen peroxide solution to the solution in the beaker
3) put the beaker on the tripod and gauze and heat the mixture in the beaker about 70 degrees
4) add 5 cm3 of cobalt II chloride solution to the mixture in the beaker
5) when the reaction has finished, add another 2cm3 of hydrogen peroxide

Question 2

what are the signs of the reactions?

Answer 2

when cobalt II chloride solution is added it goes muddy green and then bright pink

Question 3

what happens when hydrogen peroxide is added again?

Answer 3

process repeats again and the catalyst does it’s job again

Question 4

why is the uncatalysed reaction slow?

Answer 4

activation energy is too high

Question 5

what observations lead to the conclusion that cobalt II ions are acting as a catalyst?

Answer 5

colour comes back, catalyst is regenerated