Section 6 - Groups in the Periodic Table - Groups 1, 7, 0 and halogen displacement

Question 1

Order of all group 1 metals from least to most shells? What are they known as?

Answer 1

Alkali metals

Lithium ==> Sodium ==> Potassium ==> Rubidium ==> Caesium ==> Francium

Question 2

2 physical properties of group 1 metals?

Answer 2

Low melting and boiling points (compared with other metals) and very soft (can be cut with knife)

Question 3

As you go down group 1, how do the elements get more reactive?

Answer 3

Outer electron is more easily lost as it’s further from nucleus so it’s less strongly attracted to nucleus and less energy needed to remove it

Question 4

What is produced when an alkali metal reacts with water?

Answer 4

Alkali metal + water –> metal hydroxide + hydrogen

Question 5

What will you see when potassium reacts with water?

Answer 5

Fizzing, it will ignite and move around surface

Question 6

What happens to melting points and density as you go down group 1?

Answer 6

Melting points decrease and density increases

Question 7

What are group 7 elements know as?

Answer 7

The Halogens

Question 8

Order of all group 7 elements from least to most shells?

Answer 8

Fluorine ==> Chlorine ==> Bromine ==> Iodine ==> Astatine

Question 9

What type of molecules do the halogens exist as?

Answer 9

Diatomic molecules (e.g. Cl2, Br2, I2)

Question 10

What happens to melting points and density as you go down group 7?

Answer 10

Both increase

Question 11

Colour of chlorine, bromine and iodine and state? Poisonous?

Answer 11

Cl - Green gas, poisonous
Br - Red-brown liquid which gives off an orange vapour, poisonous
I - Dark grey crystalline solid which gives off a purple vapour when heated

Question 12

How can you test for chlorine gas?

Answer 12

Collect gas in test tube and hold piece of damp blue litmus paper over it. If litmus paper turns red, then bleaches white, chlorine is present

Question 13

Why does reactivity decrease as you go down group 7?

Answer 13

It gets harder to attract the extra electron to fill outer shell when shell is further away from nucleus so it’s less attracted to nucleus and needs more energy

Question 14

What do halogens form when they react with some metals or hydrogen?

Answer 14

With metal - salts called metal halides

With hydrogen - Hydrogen halides

Question 15

What is a displacement reaction?

Answer 15

Where a more reactive element ‘pushes out’ (displaces) a less reactive element from a compound

Question 16

What kind of reactions are halogen displacement reactions?

Answer 16

Redox reaction. Halogens gain electrons (reduction) whilst halide ions lose electrons (oxidation)

Question 17

What are group 0 element known as?

Answer 17

Noble gases

Question 18

4 features of group 0 elements?

Answer 18

Colourless, monatomic, inert, non-flammable

Question 19

Why is argon used in filament lamps?

Answer 19

It’s non-flammable so stops hot filament from burning away

Question 20

Why are argon and helium used to protect metals that are being welded?

Answer 20

Inert atmosphere stops hot metal reacting with oxygen

Question 21

Why is helium used in airships and party balloons?

Answer 21

Has a lower density than air so floats object. Also non-flammable so safer to use than hydrogen gas

Question 22

What happens to melting and boiling points and density as you go down group 0?

Answer 22

Both increase

Question 23

Order of group 0 elements from least to most shells?

Answer 23

Helium ==> Neon ==> Argon ==> Krypton ==> Xenon ==> Radon