DP Chemistry (last assessment 2024)
Question 18M.2.hl.TZ1.g.i
Date | May 2018 | Marks available | [Maximum mark: 2] | Reference code | 18M.2.hl.TZ1.g.i |
Level | hl | Paper | 2 | Time zone | TZ1 |
Command term | Describe | Question number | g.i | Adapted from | N/A |
g.i.
[Maximum mark: 2]
18M.2.hl.TZ1.g.i
Calcium carbide, CaC2, is an ionic solid.
Describe how sigma (σ) and pi () bonds are formed.
[2]
Markscheme
sigma (σ):
overlap «of atomic orbitals» along the axial/internuclear axis
OR
head-on/end-to-end overlap «of atomic orbitals»
pi ():
overlap «of p-orbitals» above and below the internuclear axis
OR
sideways overlap «of p-orbitals»
Award marks for suitable diagrams.
[2 marks]