Group 2 boo boo

Question 1

whats an alternate name for group two metals

Answer 1

alkaline earth metals

Question 2

what is the trend in atomic radius and why

Answer 2

increases down the group
more electrons
more energy levels
bigger distance
larger nuclear charge is less imp

Question 3

explain the trend in reactivity

Answer 3

increases down group two
more sheilding
less attraction between outr electron and nucleus
easier to remove( less energy required)
more reactive

Question 4

explain the trend in 1st ionisation energy

Answer 4

decreases down the group
easier to remove outer electron
more sheilding
less attraction between outer electron and nucleus

Question 5

describe the trend in melting

points

Answer 5

• decrease down the group
• less attraction between deloc electrons and positive ions due to larger atomic radius

-there for weaker metallic bonding

Question 6

describe the reaction of an group 2 metal with water and also with oxygen

Answer 6

metal+ water= metal hydroxide (oh)2 + hydrogen

metal+oxide=metal oxide

Question 7

what are the solubulity rules of group 2 metal sulphates and hydroxides

Answer 7

sulphates —descrease solubility down the group

hydroxides—-increase solubility down the grouo

Question 8

describe extraction of titanium and why its trickier than usual

Answer 8

ti can be reacted with carbon or will produce ti carbonate which is weak etc
so step 1
make ticl4 by reaction tio2 (rutile) with carbon in a stream of cl
step 2
react ticl4 with mg for a replacement / substitution reaction to leave ti and mgcl4
conditions must be mg liquid and 1200degrees in inert(no oxy) atmosphere

Question 9

how do you test for sulphate ions

Answer 9

• add dilute hcl to acidify solution and remove carbonate impurities
• add bacl and white precip (baso4) will form if sulphate present

Question 10

what are 3 uses for group 2 metals

Answer 10

• barium sulphate–>barium meal due to low solubility
• milk of magnesia —> acidifies stomach acid
• Slaked lime—> neutralises acidic soil