DP Chemistry (last assessment 2024)
Question 18M.2.hl.TZ2.3d
| Date | May 2018 | Marks available | [Maximum mark: 2] | Reference code | 18M.2.hl.TZ2.3d |
| Level | hl | Paper | 2 | Time zone | TZ2 |
| Command term | Explain | Question number | d | Adapted from | N/A |
d.
[Maximum mark: 2]
18M.2.hl.TZ2.3d
The emission spectrum of an element can be used to identify it.
(d)
Explain why transition metals exhibit variable oxidation states in contrast to alkali metals.
[2]
Markscheme
Transition metals:
«contain» d and s orbitals «which are close in energy»
OR
«successive» ionization energies increase gradually
Alkali metals:
second electron removed from «much» lower energy level
OR
removal of second electron requires large increase in ionization energy
[2 marks]