Topic 6- Groups in the periodic table (with spec) paper 2

Question 1

What are elements called which are in group 1?

Answer 1

Alkali metals

Question 2

What are elements called which are in group 7?

Answer 2

Halogens

Question 3

What are elements called which are in group 0?

Answer 3

Noble gases

Question 4

What do all alkali metals have in common?

Answer 4

They all have 1 electron in their outer shell

Question 5

What are the electron configurations of the first three alkali metals?

Answer 5

2.1, 2.8.1, 2.8.8.1

Question 6

What are the properties of alkali metals?

Answer 6

Soft, low melting points, float, form ionic compounds

Question 7

What is the reaction of lithium and water like?

Answer 7

Move around the surface, fizzing

Question 8

What is the reaction of sodium and water like?

Answer 8

moves around the surface, fizzes, melts in the heat of the reaction

Question 9

What is the reaction of potassium and water like?

Answer 9

moves around the surface, fizzes, melts, potassium gets so hot that it ignite the hydrogen gas

Question 10

what happens when alkalis react in cold water?

Answer 10

it produces a hydroxide and hydrogen gas. eg. sodium + water = sodium hydroxide + hydrogen

Question 11

Why do the alkali metals get more reactive as you go down the group?

Answer 11

As it is easier to lose electrons from its outer shell as its further from the nucleus so is less attracted and they all have 1 electron in their outer shell so is easier to lose

Question 12

What is the colour and physical state of chlorine at room temperature?

Answer 12

poisonous green gas

Question 13

What is the colour and physical state of bromine at room temperature?

Answer 13

red-brown liquid, gives off an orange vapour

Question 14

What is the colour and physical state of iodine at room temperature?

Answer 14

dark grey solid which gives off a purple vapour when heated

Question 15

What do the halogens all have in common?

Answer 15

They have 7 electrons on their outer shell

Question 16

State the trend in reactivity of the halogens as you go down group 7

Answer 16

• They get less reactive as the outer shell is going further away from the nucleus so harder to attract electrons
• Darker
• Melting point increases

Question 17

What is the chemical test for chlorine?

Answer 17

hold damp blue litmus paper over it and it should bleach white. it may go red for a moment as a chlorine solution is acidic.

Question 18

What happens when you react the halogens with metals?

Answer 18

They form metal halides e.g., chlorine + hydrogen = hydrogen chloride

Question 19

When the halogens form hydrogen halides what happens when they then dissolve in water?

Answer 19

They form acidic solutions. e.g. hydrogen chloride + water = hydrochloric acid

the hydrogen halides are soluble and dissolve in the water to form an acidic solution

Question 20

What is the number in the bottom of an element representing?

Answer 20

The number of electrons and protons separately

Question 21

What is the number above an element representing?

Answer 21

The number of protons and neutrons added together

Question 22

The more the electrons….

Answer 22

the further the outer shell is from the nucleus. This means it is more reactive as the decrease in attraction between the nucleus and outer shell makes it easier to get rid of the outer shell electrons.

Question 23

How many electrons do halogens have on their outer shell?

Answer 23

7. This means they will want to gain 1 electron to form a full outer shell. They will gain an electron to form a - ion

Question 24

What halogens go round in?

Answer 24

Pairs. They are diatomic molecules.

Question 25

Why are displacement reactions are redox reactions in terms of gain and loss of
electrons?

Answer 25

Displacement reactions are examples of redox reactions: the halogens gain electrons (reduction) and the halide ions lose electrons (oxidation)
eg. if you add chlorine water to potassium bromide solution, the chlorine will displace the bromine from the salt solution

Question 26

Write the ionic equation for potassium and water

Answer 26

2K(g) + H20(L) = K20(aq) + 2H(g)

Question 27

What colour would chlorine, bromine and iodine water turn universal indicator to?

Answer 27

Red

Question 28

Which is the most reactive halogen?

Answer 28

Fluorine

Question 29

Why don’t noble gases react?

Answer 29

Because they have a full outer shell

Question 30

What are the properties of the noble gases?

Answer 30

monatomic- their gases are made up of single atoms (not molecules)
inert- due to their full outershell
non-flammable- due to their inert nature

Question 31

What property of helium is good for balloons?

Answer 31

Lower density than air so it makes balloons float. it is also non-flammable which makes it safer than hydrogen gas.

Question 32

What property of argon makes it good for filament light bulbs?

Answer 32

Doesn’t react with oxygen so is non-flammable so stops the hot filament from burning away.

Question 33

Write the electron configurations of the first three noble gases

Answer 33

2.0, 2.8, 2.8.8, they all have a full outer shell.

Question 34

What are the first three noble gases?

Answer 34

Helium, neon, argon

Question 35

What are the first three alkali metals?

Answer 35

Lithium, sodium, potassium

Question 36

What are the first four halogens?

Answer 36

Fluorine, Chlorine, bromine, iodine

Question 37

what do halogens take part in?

Answer 37

halogen displacement reactions. the halogens gain electrons and their halide ions lose their electrons.i f you add a halogen to a solution lower down the table then it will be displaced.

Question 38

describe the trend in reactivity of halogens

Answer 38

the halogens get less reactive as you go down the group. you could use this to predict astatine as the least reactive halogen and that it won’t displace any other halogens from their salt solutions.

Question 39

how can you see the displacement reactions with halogens and the solutions of the salts?

Answer 39

mix different combinations of chlorine, bromide and iodine with solutions of the salts potassium chloride, potassium iodide and potassium bromide and see if there is a reaction which happens (through a colour change). if there is a colour change then there has been a displacement reaction.

Question 40

what do the electronic configurations of the halogens tell about their reactivity?

Answer 40

they become less reactive as you go down as the outer shell is further from the nucleus meaning its harder to attract the extra electron.

Question 41

explain the pattern in the physical properties of noble gases

Answer 41

• bp, mp and density all increase as you go down group 0

Question 42

knowing the reactivity of lithium, sodium and potassium, what would the reactivity of rubidium be like in water?

Answer 42

it will react more violently with water and could explode

Question 43

what can you use halogen displacement reactions to find out and how should you do it?

Answer 43

you can use these displacement reactions to show the reactivity trend of the halogens

1) measure out the halide salt solution (eg. potassium chloride solution)
2) add a few drops of the halogen solution (eg. chlorine water) and shake
3) if you see a colour change then a reaction has taken place and the halogen has displaced the halide ions from the salt

Question 44

what happens as you go down group 0

Answer 44

bp, mp and density increase

Question 45

What are the extra properties of transition metals?

Answer 45

• variable oxidation states (the ions can have different charges)
• they can be used as catalysts
• form coloured compounds