Periodicity: Group 2, Alkaline Earth Metals - Trends Flashcards
1
Q
Describe the trend in atomic radius as you descend group 2
A
- Atomic radius increases
- Number of electron shells increase as you descend group
2
Q
Describe the trend in first ionisation energy as you descend group 2
A
- First ionisation energy decreases
- More electron shells, means outer electrons are further away from nucleus
- Increased shielding
- Weaker attraction of ion to lost electrons
3
Q
Describe the trend in reactivity as you descend group 2
A
- When group 2 elements react, they lose electrons, forming positive ions
- The easier it is to remove electrons (the lower the first ionisation energy), the more reactive the element
- Reactivity increases down the group
4
Q
Describe the trend in melting point from Mg-Ba
A
- Melting points generally decrease (Mg decreases by a significant amount)
- Metallic bonds are weaker
- Size of the metal ion increases, resulting in less attraction between the nucleus of the positive ions and the delocalised electrons
5
Q
Describe the trend in reactivity with water as you descend group 2
A
- Reactivity with water increases