DP Chemistry (last assessment 2024)
Question 19M.3.hl.TZ1.b(ii)
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.3.hl.TZ1.b(ii) |
| Level | hl | Paper | 3 | Time zone | TZ1 |
| Command term | Suggest | Question number | b(ii) | Adapted from | N/A |
b(ii).
[Maximum mark: 1]
19M.3.hl.TZ1.b(ii)
Physical properties of elements vary according to atomic number. Sections 6 to 9 of the data
booklet list some of these properties.
Melting points and boiling points of elements 1 to 95
Suggest, with a reason, whether the lanthanoids or actinoids of the f-block would have the higher density.
[1]
Markscheme
actinoids AND density increases down all groups «due to large increase in atomic mass for small increase in atomic volume»
OR
actinoids AND «much» greater atomic mass with similar type of bonding
OR
actinoids AND density «of actinoids» atomic number 90 to 95 is greater than corresponding lanthanoids [✔]
Note: Accept “actinoids AND on graph actinoids have «much» greater density than lanthanoids”.
