Group 2

Question 1

Group 2

Answer 1

Earth alkali metals

Question 2

Properties (gp2)

Answer 2

Shiny when freshly cut
Tarnish upon exposure to O2
Soft (harder down group)
Low density (increases down gp)
Electrical conductors

Question 3

Appearance of gp2 metals

Answer 3

Shiny when freshly cut
Tarnish when exposed to o2 as reactive so forms thin oxide layer

Question 4

Softness (gp2)

Answer 4

Softness increases going down
Weaker metallic bond due to increase in shielding

Question 5

First ionisation energy going down (gp2)

Answer 5

More shells so atomic radius increases going down
More shielding experienced
So easier to lose electron going down

Question 6

Metallic bonding

Answer 6

Electrostatic attraction between positive metal ions and negative delocalised electron

Question 7

Melting point and boiling point (gp2)

Answer 7

Decreases down group
Larger atomic size
distance between positive metal ions and delocalised electrons increases
Lower charge density
Weaker metallic bonding

Question 8

Reaction w water equation

Answer 8

X(s) + 2H2O(l) -> X(OH)2(aq) +H2 (g)

Question 9

Reaction w steam equation

Answer 9

X(s) + H2O(g) ~> XO(s) + H2

Question 10

Trend in reactivity in water (gp2)

Answer 10

Reactivity Increases going down
As atomic size increases
So larger atomic radius
Weaker metallic attraction between positive ion and delocalised electron

Question 11

Beryllium w water liquid

Answer 11

Little to no reaction

Question 12

Beryllium w steam

Answer 12

Vigorous heating or reaction w steam
produces white solid (beryllium oxide)
h2 gas bubbles

Question 13

Mg w cold water

Answer 13

Slow reaction
White ppt
Colourless gas bubbles (h2)

Question 14

Mg w steam

Answer 14

Burns w white flame
Produces white solid (MgO)
H2 gas bubbles

Question 15

Calcium w water

Answer 15

Reacts vigorously
Produces white solid that dissolves in water to form clear colourless limewater Ca(OH)2
H2 gas bubbles

Question 16

Calcium w steam

Answer 16

Vigorous reaction
Bright flame
White solid CaO
H2 bubbles

Question 17

Using Mg q

Question 18

MgSO4 test

Answer 18

Prepare sample solution
Add few drops of Barium Hydroxide
Positive test = white ppt forms
Because barium Sulfate is insoluble in water

Question 20

Test for sulfate ions

Answer 20

Reagent: barium chloride
Adding few drops of HCL
Adding few drops of BaCl2

Positive test: white ppt of barium sulfate forms

Question 21

Group2 + HCl

Answer 21

Reacts vigorously

Question 22

Ca + H2SO4

Answer 22

Reactions slowed stopping H bubbles from rising

Question 23

Group 2 metals

Answer 23

Group 2 sulfate become sulfates become less soluble down group

Question 24

Barium sulfate use

Answer 24

Insoluble
So used for x ray imaging to view digestive system to show outline of organs

Question 25

Hcl and bacteria

Answer 25

HCl is strong acid Lowers the pH disrupting microorganism environment Denaturing enzymes and proteins Killing bacteria

Question 26

Halide rest

Question 27

Using magnesium to extract titanium

Answer 27

c can extract titanium but forms carbide (brittle) So titanium oxide converted to chloride which is reduced w mg

Question 28

Using magnesium to extract titanium equation

Answer 28

TiCl4 + 2Mg -> Ti + 2MgCl

Question 29

Why is group two called earth alkali metals

Answer 29

They produce alkaline X(OH)2 solutions when reacted w water

Question 30

Saturated solution meaning

Answer 30

Excess solid added