Elements of Group 1 and 2 - Inorganic chemistry Flashcards Preview

A Level Chemistry > Elements of Group 1 and 2 - Inorganic chemistry > Flashcards

Flashcards in Elements of Group 1 and 2 - Inorganic chemistry Deck (51)
Loading flashcards...
1

What is the bonding in the group 1 and 2 elements?

Metallic

2

What are the reasons for the trend in melting and boiling point and hardness of group 1 and 2 metals?

Metallic radius increases down the group due to the extra electron shells, so the metallic bonding weakens down the group, and so melting, boiling points and hardness all decrease down the group

3

Why are group 2 metals harder than group 1 metals and have higher melting and boiling points?

Number of valency electrons increases and metallic radius slightly decreases, so the strength of the metallic bonding increases

4

What are the reasons for the trend in ionisation energies down group 1 and 2?

The increase in nuclear charge is outweighed by the increased distance between the electron being lost and the nucleus, and the increased shielding effect of complete shells of electrons between the electron being lost and the nucleus

5

What is lithium's flame test colour?

(Carmine) red

6

What is sodium's flame test colour?

Intense yellow

7

What is potassium's flame test colour?

Lilac

8

What is magnesium's flame test colour?

No colour

9

Why does magnesium's flame test not produce a colour?

The energy emitted has a wavelength outside the visible spectrum

10

What is calcium's flame test colour?

Brick red

11

What is strontium's flame test colour?

Red/Crimson

12

What is barium's flame test colour?

(Apple) green

13

What is rubidium's flame test colour?

Red

14

What is caesium's flame test colour?

(Sky) blue

15

What is beryllium's flame test colour?

No colour

16

Why do flame tests work?

Electrons are excited to a higher energy level by the Bunsen burner flame, and as they fall back down to their ground state (they are unstable in the higher energy state), they emit energy in the form of visible light

17

How should a flame test be carried out?

1) Use a nichrome wire (very unreactive and so cannot give out a flame colour)
2) Dip the wire in concentrated hydrochloric acid (out it in the flame to check if any colour is being produced, keep cleaning it until there isn't one)
3) Grind up any solid that isn't already a powder
4) Dip the wire in the solid'
5) Put the wire into the flame so a colour is produced

18

What colour does magnesium burn in oxygen?

Intense white light

19

What colour does calcium burn in oxygen?

Brick red flame

20

What colour does strontium burn in oxygen?

Dark red flame

21

What colour does barium burn in oxygen?

Pale green flame

22

What compound do all group 2 metals form when they react with chlorine?

MCl2
Beryllium forms a covalent, anhydrous chloride, all others produce ionic chlorides

23

Beryllium's reaction with water

There is no reaction

24

Magnesium's reaction with water

Magnesium reacts very slowly with cold water, but burns when heated in steam
Mg (s) + H2O (g) -> MgO (s) + H2 (g)

25

Calcium, strontium and barium's reactions with water

React rapidly with cold water
Ba (s) + 2H2O (g) -> Ba(OH)2 (aq) + H2 (g)

26

How does the reactivity of group 2 elements change down the group?

It increases

27

Barium reacting with oxygen

2Ba (s) + O2 (g) -> 2BaO (s)

28

Beryllium oxide with water

No reaction

29

Magnesium oxide with water

MgO (s) + H2O (l) -> Mg(OH)2 (s)
Reacts slowly and incompletely to form a slightly alkaline suspension of magnesium hydroxide

30

Calcium oxide with water

CaO (s) + H2O (l) -> Ca(OH)2 (s)
Reacts very exothermically to form an alkaline suspension of calcium hydroxide (limewater)