FC13: Group 2

Question 1

What is the product of a group 2 metal with oxygen?

Answer 1

metal oxide

Question 2

What is the product of a group 2 metal with acid?

Answer 2

salt and hydrogen gas

Question 3

What is the product of a group 2 metal with water?

Answer 3

metal hydroxide and hydrogen gas

Question 4

Are group 2 metals soluble in water?

Answer 4

they are slightly soluble in water

Question 5

what happens when group 2 metals dissolve in water

Answer 5

they release hydroxide ions and form alkaline solutions

Question 6

what is the trend in alkalinity of group 2 hydroxides down the group

Answer 6

alkalinity increases down the group

Question 7

are group 2 carbonates soluble in water and what do they dissolve in?

Answer 7

insoluble in water, dissolve in acid

Question 8

What is formed when you react water and a group 2 oxide together

Answer 8

metal hydroxide

Question 9

What is formed when you add excess water in the reaction with a group 2 oxide

Answer 9

metal ion and hydroxide ions, and so an alkaline solution is formed

Question 10

what is a use of limestone (calcium carbonate)

Answer 10

limestone undergoes thermal decomposition to form quicklime (calcium oxide) which reacts with water to form calcium hydroxide (slaked lime), slaked lime is used to neutralise acidic soil for gardens/agriculture

Question 11

what are the reactions/equations for limestone to form into slaked lime

Answer 11

under heat, calcium carbonate forms solid calcium oxide and carbon dioxide
calcium oxide and water forms aqueous calcium hydroxide

Question 12

what is a use of magnesium hydroxide

Answer 12

as an antacid in indigestion remedies to neutralise excess stomach acid

Question 13

what is the reaction/equation of how magnesium hydroxide (milk of magnesia) works as an antacid

Answer 13

magnesium hydroxide and hydrochloric acid forms magnesium chloride and water and therefore neutralising the HCl

Question 14

what is a use of calcium carbonate and write the equation/reaction of how it works

Answer 14

can be used as an antacid
calcium carbonate + HCl forms calcium chloride and water and carbon dioxide

Question 15

what is an issue in using calcium carbonate as an antacid?

Answer 15

the gas produced can cause bloating/discomfort

Question 16

explain the trend of increasing alkalinity as you go down group 2

Answer 16

the hydroxides increase in solubility as you go down the group and so dissociate hydroxide ions more readily hence the increasing pH down the group

Question 17

state and explain the rate at which hydrogen is produced if you use calcium instead of magnesium if you react it with HNO3, and what difference in volume of hydrogen would be produced although using same number of moles

Answer 17

would increase because calcium has a lower ionisation energy than magnesium
a higher volume of hydrogen would be produced because calcium reacts with water in the aqueous acid to produce extra H2

Question 18

why would barium hydroxide or sodium carbonate be less suited to use as indigestion treatments compared to magnesium hydroxide or calcium carbonate

Answer 18

they are both very soluble compared to the others and so the liquid in the mouth/stomach would be too alkaline resulting in damage

Question 19

state and explain the ionisation energy trend down group 2

Answer 19

decreases, because number of electron shells increases down group 2, the greater shielding effect outweighs the greater nuclear charge, and so atomic radius increases down group 2, and so the outermost electrons are further away from nucleus as you go down group 2 and so the attraction between the nucleus and the outermost electrons decreases as you go down the group and so ionisation energy decreases down group 2