Topic 6 - Groups In The Periodic Table

Question 1

What are the group 1 metals?

Answer 1

Alkali metals

Question 2

How can elements be classified as alkali metals based on their position on the periodic table?

Answer 2

They all have one outer electron on their outer shell so they’re group 1

Question 3

How can elements be classified as halogens based on their position on the periodic table?

Answer 3

They all have 7 electrons in their outer shell so are in group 7

Question 4

How can elements be classified as noble gases based on their position on the periodic table?

Answer 4

They have a full outer shell so are group 0

Question 5

Physical properties of alkali metals

Answer 5

Low melting and boiling points

Very soft

Question 6

Describe the reaction of lithium with water

Answer 6

Lithium will move around the surface, fizzing furiously

Question 7

Describe the reaction of sodium with water

Answer 7

Move around quickly and fizz. Also melts in the heat of reaction

Question 8

Describe the reaction of potassium with water

Answer 8

Moving around violently and fizzes. Gets hot enough to ignite the hydrogen produced

Question 9

Describe the pattern in reactivity of the alkali metals.

Answer 9

Reactivity increases down the group

Question 10

Explain the pattern of reactivity in group 1 in terms of electronic configurations

Answer 10

Group 1 lose their outer electron to form +1 ion. As you go down the outer electron is more easily lost because it’s further from the nucleus so it’s attraction is weaker and less energy needed to remove it

Question 11

What is chlorine at room temperature?

Answer 11

Green gas

Question 12

What is bromine at room temperature?

Answer 12

Red brown liquid which gives off an orange vapour

Question 13

What is iodine at room temperature?

Answer 13

Dark grey crystalline solid which gives off a purple vapour when heated

Question 14

What are halogens?

Answer 14

Diatomic molecules sharing one pair of electrons in a covalent bond giving both atoms a full outer shell.

Question 15

What are the trends as you go down in group 7?

Answer 15

As you go down the melting and boiling points of halogens increase. Going from gas to solid. Also colours get darker

Question 16

Describe the chemical test for chlorine

Answer 16

Hold a piece of damp blue litmus paper over chlorine. At first it turns red and then the chlorine will bleach the litmus paper white.

Question 17

Explain the relative reactivity of the halogens in terms of

electronic configurations

Answer 17

Halogen atom only gains one electron to form 1- ion. As you go down halogens become less reactive because it gets harder to attract the extra electron to fill outer shell when it’s further away from nucleus.

Question 18

What happens when halogens react with metals?

Answer 18

They react vigorously to form salts called metal halides:

Sodium + chlorine -> sodium chloride

Question 19

What happens when halogens react with hydrogen?

Answer 19

They form hydrogen halides. They’re soluble and can dissolve in water to form acidic solutions:
Hydrogen + chlorine -> hydrogen chloride

Question 20

What is a displacement reaction?

Answer 20

When a more reactive element displaces a less restive element from a compound

Question 21

What are the halogen displacement reactions?

Answer 21

They’re redox reactions. The halogens gain electrons (reduction) whilst halide ions lose electrons (oxidation)

Question 22

Why are noble gases (group 0) inert?

Answer 22

They have a full outer shell of electrons so they don’t need to give up or gain electron

Question 23

What are the uses of noble gases due to their non flammability?

Answer 23

Argon is used in filament lamps so it stops the hot filament from burning.
Some are used in flash photography to stop flash filament from burning.

Question 24

What are the uses of noble gases due to their inertness?

Answer 24

Used to protect metals that are being welded to stop the hot metal reacting with oxygen.

Question 25

What are the uses of noble gases due to their low density?

Answer 25

Helium used in balloons + airships as it has lower density than air to so it floats.

Question 26

What are the patterns in the properties of group 0?

Answer 26

As you go down group 0 BP, MP + density increase due to intermolecular forces becoming stronger

Question 27

Describe the noble gases

Answer 27

They’re a colourless gas at room temperature
Monatomic - made up of single atoms
Inert