group 2 Flashcards
what is the name of group 2?
alkaline earth metals
which sub shell is outer electron in?
2s subshell
explain trend in reactivity DOWN group 2 (4)
P- more protons
S- more shells and more shielding
D- distance between nucleus and outer shell increases
S- strength of attraction decreases
easier to remove outer 2 electrons so reactivity INCREASES going DOWN group 2
why do group 2 metals have a high boiling point?
- strong metallic bonds (strong electrostatic attraction between cations and delocalised electrons)
- requires lots of energy to overcome
give the equation of Mg and oxygen
2Mg + O2 -> 2MgO
give the equation of Mg and steam and explain why Mg cannot react with water but with steam
Mg is too unreactive, needs steam as steam has more energy
Mg + H20 (g)-> MgO (s)+ H2
give equation of Ba and water
Ba + H20 -> Ba(OH)2 + H2
give 2 observations when metal reacts with water
- solid disappears as it is used up
- effervescence as hydrogen gas forms
Metal + Acid -> ?
salt + hydrogen
define salt
when H+ of an acid is replaced with a NH4+ ion or a metal ion
give the ion of ethanoic acid
CH3COO-
Metal oxide + water -> ?
metal hydroxide
compare pH of Mg(OH)2 and Ba(OH)2
Mg(OH)2- 9 insoluble
Ba(OH)2- 13 very soluble
Ba is more alkaline and contains more OH- ions so has a higher pH
acid + alkali -> ?
salt + water
acid + base -> ?
salt + water