C1 2020

Question 1

Give two reasons why it is necessary to ionise the isotopes of chromium before they can be analysed in a TOF mass spectrometer

Answer 1

Can be accelerated
Create a current when hit the detector

Question 2

[Al(H2O)6]3+ + EXCESS NaOH

Answer 2

[Al(H2O)6]3+ + 4OH- -> [Al(OH)4]- + 6H2O

Question 3

What charge will metal EDTA be?

Answer 3

-1

Question 4

Explain with the use of an equation why a solution containing [Al(H2O)6]3+ has a pH <7

Answer 4

[Al(H2O)6]3+ + H2O <–> [Al(H2O)3(OH)]2+ + H3O+
Al3+ small size high charge density so weakens OH bond releasing H+

Question 5

State the effect if any of the addition of the catalyst on the value of kP why?

Answer 5

No effect
Catalyst does not affect position of equilibrium

Question 6

State what must be done to maintain EMF of this fuel cell when in use

Answer 6

Keep concentration of reactants constant