Topic 4

Question 1

What is the general formula when a group 2 metal (M) reacts with water?

Answer 1

M + 2H20 –> M(OH)2 +H2

Question 2

What is the trend in ionisation energy down group two

Answer 2

As you go down there is an extra electron shell so more shielding so electrons are further away from the nucleus which reduces electrostatic attraction therefore decreasing the ionisation energy

Question 3

What is the general occasion when a group to metal (M) burns in oxygen

Answer 3

2M + O2 –> 2MO

Question 4

What is the general equation when a group 2 metal (M) reacts with chlorine?

Answer 4

M+ Cl2 –> MCl2

Question 5

General equation when a group 2 metal oxide (M) reacts with water

Answer 5

MO + H2O –> M(OH)2

Question 6

General equation when a group 2 metal (M) hydroxides reacts with water?

Answer 6

M(OH)2 (s) —> M(OH)2 (l)

Question 7

Reaction between group to metal oxide (M) reacts with dilute acid

Answer 7

MO + 2HCl –> MCl2 + H2O

Question 8

General equation when a group two metal hydroxide (M) reacts with dilute acid?

Answer 8

M(OH)2 + 2HCl –> MCl2 + 2H2O

Question 9

Why does thermal stability increase down a group?

Answer 9

As you go down the group the cations get bigger so there is less distortion by anions such as carbonates or nitrates this makes them more thermally stable

Question 10

Which group is more thermally stable group 1 or group 2 and why?

Answer 10

Group 2 has a greater charge so there is greater distortion so less thermally stable therefore group one is more thermally stable

Question 11

Group 1 carbonates are thermally stable but what is the exception

Answer 11

Lithium carbonate

Question 12

Group 1 nitrates decomposes to form what

Answer 12

The metal nitrate and oxygen gas

Question 13

Group 2 carbonates decompose to form what

Answer 13

The metal oxide and carbon dioxide gas

Question 14

Group 2 nitrites decomposes to form what

Answer 14

The metal oxide, nitrogen dioxide, and oxygen

Question 15

What colour is lithium in a flame test

Answer 15

Red

Question 16

What colour is sodium in a flame test?

Answer 16

Orange/yellow

Question 17

What colour is potassium in a flame test

Answer 17

Lilac

Question 18

What colour is calcium in a flame test

Answer 18

Brick red

Question 19

What colour is Rubidium in a flame test

Answer 19

Red

Question 20

What colour is the caesium in a flame test

Answer 20

Blue

Question 21

What colour is strontium in a flame test

Answer 21

Crimson

Question 22

What colour is barium in a flame test

Answer 22

Green

Question 23

What colour is magnesium in a flame test

Answer 23

It doesn’t produce a colour

Question 24

Why does the flame tests produce different colours

Answer 24

Energy is absorbed from the flame as electrons move to higher energy levels. The colours of seen when the electrons fall back down to lower energy level is releasing energy in form of light

Question 25

Why do you halogens gets less reactive when you go down the group

Answer 25

The atoms become larger so electrons are further from the nucleus, there is also shielding. This makes it harder for large atoms to attract the electron they need.

Question 26

Explain the trend in melting and boiling points as you go down group 7

Answer 26

As you go down group 7 there is an increase in electron shells. This means there are more London forces so the melting and boiling points are higher to overcome the intermolecular forces

Question 27

What ions can chlorine displace

Answer 27

Bromide and iodide

Question 28

What is the equation when sodium hydroxide reacts with chlorine

Answer 28

2NaOH(Aq) + Cl2 (g) --> NaClO (Aq) + NaCl (Aq) + H2O (l)

Question 29

What is the general equation when halogen (X) reacts with a hot alkali?

Answer 29

3X2 + 6NaOH --> NaXO3 + 5NaX + 3H2O