Group II

Question 1

What is the definition of an s-block element

Answer 1

An element which has an atom with the highest energy/outer shell electron in an s subshell

Question 2

What are he physical properties of group II metals

Answer 2

• atomic radius increases as group descends

- 1st ionisation energetic decreases as you descend group - increased radius and shielding

Question 3

What is the equation when metal oxides react with water

Answer 3

Metal oxide + water = metal hydroxide

Question 4

What is the equation when metal oxides react with acid

Answer 4

Metal oxide + acid = salt + water

Question 5

State two uses of group II compounds

Answer 5

⭕️ MgO - cure indigestion - reacts with excess stomach acid

⭕️ CaCO3 - toothpaste - neutralises acid on teeth

Question 6

What is a use of calcium carbonate

Answer 6

Makes limewater:
Limestone heated - thermal decomposition to calcium oxide
Calcium oxide mixed with water to form calcium hydroxide (limewater)

Question 7

What is cement made of

Answer 7

Calcium oxide and silica

Question 8

What happens when water is added to calcium oxide and silica

Answer 8

Makes calcium silicate

Question 9

What happens when aluminium oxide reacts with calcium oxide

Answer 9

Makes calcium aluminate

Question 10

What happens when water evaporates from calcium silicate and calcium aluminate

Answer 10

They crystallise and form solid cement

Question 11

What is concrete

Answer 11

Cement with gravel and more sand added

Question 12

What is the equation for the thermal decomposition of metal carbonate

Answer 12

Metal carbonate ➡️ metal oxide + carbon dioxide

Question 13

What is the trend for decomposition temperature as you descend group II

Answer 13

Increases down group

Question 14

Why does thermal decomposition temperature increase down group II carbonates and hydroxides

Answer 14

• Size of cation increases
• Charge density decreases
• Cation less able to polarise and destabilise carbonate ion
• therefore more thermally stable

Question 15

What is the general equation for the decomposition of metal hydroxides

Answer 15

Metal hydroxide ➡️ metal oxide + water

Question 16

What is the trend for thermal decomposition temperature for metal hydroxides as you move down group II

Answer 16

Increases

Question 17

What is the trend of solubility of group II sulphates as you move down the group

Answer 17

Solubility decreases down group

Question 18

What is the trend of solubility of group II hydroxides as you move down the group

Answer 18

Solubility of hydroxides increases down the group

Question 19

What happens to the solubility of solids as temperature increases

Answer 19

Solubility increases

Question 20

What happens to gaseous solutes as temperature increases

Answer 20

Solubility decreases

Question 21

What is the trend for reactivity we you go down group II

Answer 21

Increases

Question 22

What is the general equation for the reaction of steam with a group II metal. Also write the general symbol equation

Answer 22

Metal + steam = metal oxide + hydrogen

See page 87 revision book

Question 23

What colour will magnesium burn with steam

Answer 23

White light

Question 24

What colour does calcium burn with when reacted with steam

Answer 24

Red

Question 25

What colour does strontium burn when reacted with steam

Answer 25

Red flame

Question 26

What colour does barium burn with when reacted with steam

Answer 26

Green

Question 27

What is the general equation for the reaction of group II elements with water. Write the symbol equation also

Answer 27

Metal + water = metal hydroxide + hydrogen | See page 87 rev book for symbol equation

Question 28

What are the observations when Mg reacts with water

Answer 28

Bubble very slowly | Metal dulls in appearance

Question 29

What are general observations for Ca, Sr and abs when they react with water

Answer 29

Bubbles Heat Eventually disappear

Question 30

What are the observations when calcium reacts with cold water

Answer 30

Gives sparingly soluble white hydroxide | Sinks and rises

Question 31

What are the observations when Sr reacts with cold water

Answer 31

Vigorous | Gives sparingly soluble white hydroxide - completely soluble in hot water

Question 32

What are the observations when Ba reacts with water

Answer 32

V vigorous | Forms white hydroxide- moderately soluble in water

Question 33

What is the general equation when group II elements react with oxygen. Write the symbol version too

Answer 33

Metal + oxygen ➡️ metal oxide | See page 86 revision book

Question 34

What are the observations for Mg, Ca, Sr and Ba when they react with oxygen

Answer 34

``` All produce white powder Mg = bright white light Ca = brick red flame Sr = red flame Ba = green flame ```

Question 35

What is the general and symbol equation for the reaction between group II elements and acids. (Both HCl and H2SO4)

Answer 35

Metal + acid = metal salt + hydrogen | See page 88 rev book

Question 36

What are the observations for the reaction of group II metal and acid

Answer 36

Heat released Bubbles Metal disappears Colourless solution formed