Gp 2 Flashcards
(9 cards)
1
Q
Explain why melting point decreases down the group
A
- down the group size of ion increases, charge density decreases
-shielding effect increases but number of delocalised e per atom is constant
- attraction between cations and electrons decreases causing strength of metallic bond to decrease
2
Q
Why does reactivity increases down group 2
A
- atomic size increases
- shielding effect
- outermost electrons are less and less attracted to the nucleus
Thus, the activation energy for the reactions down the group decreases
3
Q
Colour of flame of magnesium
A
White dazzling flame
4
Q
Colour of flame of calcium
A
Brick red
5
Q
Colour of flame of strontium
A
Crimson red
6
Q
Colour of flame of barium
A
Green
7
Q
What colour is the oxide formed for group 2
A
White solid
8
Q
Reaction of magnesium and cold water
A
Gives magnesium hydroxide and hydrogen
9
Q
Reaction of magnesium and stream
A
Gives magnesium oxide and hydrogen
Bright white flame
White ppt
