CAIE A-Level Chemistry 1.2.4 Physical Properties of Isotopes
Practise explaining why isotopes differ in mass and density while retaining the same chemistry.
- Syllabus
- 2028–2030
- Course
- Chemistry 9701
- Level
- AS
Practise explaining why isotopes differ in mass and density while retaining the same chemistry.
Calcium, magnesium and radium are Group 2 elements. Radium follows the same trends as the other members of Group 2.
A sample of magnesium contains three isotopes, 25Mg,26Mg and X.
The percentage abundance of the three isotopes is shown in Table 1.1.

Table 1.1
State one similarity and one difference in the properties of these isotopes of magnesium. Explain your answer.
M1 (magnesium isotopes have) identical chemical properties
AND same electron(ic) arrangement / configuration
M2 different physical properties AND different number of neutrons