Chemistry of the Elements

Question 1

The rows of the periodic table are called …. The properties of elements … as you go along a period

Answer 1

The rows of the periodic table are called periods. The properties of elements change as you go along a period

Question 2

The columns of the periodic table are called …

Answer 2

The columns of the periodic table are called groups

Question 3

What do elements in the same group have in common? Why? What changes?

Answer 3

elements in the same group have similar chemical properties

this is because they have the same number of electrons on their outer shell

the proprties of elements (such as reactivity) often gradually change as you go down a group (i.e. as the atomic number increases)

Question 4

Do you metals conduct electricity? Why?

Answer 4

(they are the green)

metals conduct electricity because they allow charge to pass through them easily

Question 5

Metal oxides are basic. What does this mean?

Answer 5

(they are the green)

this means they wil neautralise acids

metal oxides which dissolve will form solutions of a pH of more than 7

Question 6

Do non-metals conduct electricity?

Answer 6

(they are the blue)

non-metals are poor conductors of electricity

Question 7

Non-metals are acidic. What does this mean?

Answer 7

(they are the blue)

this means they dissolve in water to form solutions with a pH of less than 7

Question 8

What state of matter do metals tend to be?

Answer 8

solids

e.g. mercury is an exception - it is a liquid

Question 9

What are the differences in melting and boiling points between metals and non-metals?

Answer 9

metals tend to have high melting and boiling points

non-metals tend to have low metling and boiling points (carbon and silicon are obvious exceptions)

Question 10

Do metals tend to have relatively low or relatively high densities?

Answer 10

metals tend to have relatively high densities

Question 11

Metals are … when they are polished (known as metallic …), and tend to be easily …

Answer 11

Metals are shiny when they are polished (known as metallic lustre), and tend to be easily workable

Question 12

Non-metals tend to … as solids and, even if they are crystalline, they don’t have the same sort of … a metals

Answer 12

Non-metals tend to brittle as solids and, even if they are crystalline, they don’t have the same sort of shinea metals

Question 13

What is the difference in conducting electricity and heat in metals and non-metals?

Answer 13

metals are good conductors of electricity and heat

non-metals usually don’t conduct electricity - carbon (in the form of graphite) and silicon are exception

non-metals are poor conductors of heat

Question 14

Metals form … ions in their compounds. Non-metals form … ions and … compounds

Answer 14

Metals form positive ions in their compounds. Non-metals form negative ions and covalent compounds

Question 15

What is Group 0? Which elements are in it?

Answer 15

the noble gases

(in order):
helium

neon

argon

krypton

xenon

radon

Question 16

Noble gases are coloured/colourless gases

Answer 16

Noble gases are colourless​ gases

Question 17

What percentage of the air is made up of Argon?

Answer 17

nearly 1%

Question 18

Helium has the … density of any gas

Answer 18

Helium has the second lowest density of any gas (after hydrogen)

Question 19

All noble gases are monatomic/diatomic. What does this mean?

Answer 19

All noble gases are monatomic

This means that their molecules consist of single atoms

Question 20

The density and boiling point of noble gases increases/decreases as you down the Group

Why is this?

Answer 20

The density and boiling point of noble gases increases as you down the Group

this is because the attractions between one molecules and its neighbour get stronger as the atoms get bigger

more energy is needed to break the stronger attractions

Question 21

Noble gases do/don’t form stable ions, and so do/don’t produce ionic compounds

Answer 21

Noble gases don’t form stable ions, and so don’t produce ionic compounds

Question 22

Noble gases are/aren’t inert. What does this mean? Why?

Answer 22

Noble gases are ​inert

this means they don’t react with much at all

this is because they have a full outer shell of electrons

Question 23

What is Group 1 of the periodic table? What elements are in it?

Answer 23

the alkali metals

(in order):

lithium

sodium

potassium

rubidium

caesium

francium

Question 24

The alkali metals have low/high melting and poling points (for metals), and get lower/higher as you go down the group

Their densities tend to … as you go down the group

Answer 24

The alkali metals have low melting and poling points (for metals), and get lower as you go down the group

Their densities tend to increase as you go down the group

Question 25

Which alkali metals float on water? Why?

Answer 25

lithium, sodium and potassium are less dense than water, so they will float

Question 26

The alkali metals are very soft/hard and get softer/harder as you go down the group

They are … but … within seconds of exposure to air

Answer 26

The alkali metals are very soft and get softer as you go down the group

They are shiny but tarnish within seconds of exposure to air

Question 27

How must the alkali metals be stored?

Answer 27

they have to be stored out of contact with air or water, so they are stored under oil

Question 28

When lithium, sodium and potassium are put in water, how do they react?

Answer 28

they react vigorously

Question 29

What does the reaction of an alkali metal with water produce? Is this alkaline or acidic?

Answer 29

a metal hydroxide and hydrogen

this solution is alkaline

Question 30

What does aqueous (aq) mean?

Answer 30

dissolved in water

Question 31

What is the word and symbol equation for the reaction of sodium with cold water?

Answer 31

sodium + cold water → sodium hydroxide + hydrogen

2Na _(s) + 2H₂O _(l) → 2NaOh _(aq) + H_{2 (g)}

Question 32

Alkali metals have mainly … (a colour) compounds which dissolve to produce coloured/colourless solutions

Answer 32

Alkali metals have mainly whit compounds which dissolve to produce colourless solutions

Question 33

As you go down Group 1, the elements become less/more reactive as the atomic number increases/decreases

Answer 33

As you go down Group 1, the elements become more reactive as the atomic number increases

Question 34

What is observed in the reaction of lithium with water? What colour does the universal indicator turn?

Answer 34

the lithium moves slwowly around rge surface, fizzing, until it disappears

the indicator turns from neutral to purple because the water has become alkaline

Question 35

What is observed in the reaction of sodium with water? What colour does the universal indicator turn?

Answer 35

sodium fizzed rapidly and moves quickly around the surface, it may ignite

it reacts faster than lithium

the indicator turns from neutral to purple because the water has become alkaline

Question 36

What is observed in the reaction of potassium with water? What colour does the universal indicator turn?

Answer 36

potassium reacts vigorously, burns with a lilac flame - and sometimes explodes

potassium reacts faster than lithium and sodium

the indicator turns from neutral to purple because the water has become alkaline

Question 37

Group 1 metals have … electron on their outer shell

As you go down Group 1, the outermost electron is in a shell that is closer/further from the nucleus. What does this mean?

What charge are their ions?

Answer 37

Group 1 metals have oneelectron on their outer shell

As you go down Group 1, the outermost electron is in a shell that is further from the nucleus

This means that as the atom gets bigger as you go down the group, the attraction between the outermost electron and the nucleus becomes loess and the outer electron is lost more easily, and the metals are move reactive

Their ions are +1 charged

Question 38

What is Group 7? What elements are in it?

Answer 38

halogens

(in order):

fluorine

chlorine

bromine

iodine

astatine

Question 39

The halogens are monatomic/diatomic

Answer 39

The halogens are diatomic​

Question 40

What state of matter and colour is flourine?

Answer 40

gas

yellow

Question 41

What state of matter and colour is chlorine?

Answer 41

gas

green

Question 42

What state of matter and colour is bromine?

Answer 42

liquid

dark red liquid - red/brown vapour

Question 43

What state of matter and colour is iodine?

Answer 43

solid

dark grey solid - purple vapour

Question 44

The halogens are good/poor conductors of heat and electricity

When they are solid, their crystals will/will not be brittle

Answer 44

The halogens are poor conductors of heat and electricity

When they are solid, their crystals will be brittle

Question 45

As the atomic number of the halogens increased, the elements have a lighter/darker colour and a lower/higher boiling point

Answer 45

As the atomic number of the halogens increased, the elements have a darker colour and a higher boiling point

Question 46

As you go up Group 7, the reactivity increases/decreases. Why?

Answer 46

As you go up Group 7, the reactivity increases

this is because the shell with the missing electron is nearer to the nucleus, so the attraction to to positive nucleus is greater

Question 47

What do the halogens react with hydrogen to form?

Answer 47

hydrogen halides

Question 48

What three things are hydrogen halides? How are they bonded?

Answer 48

steamy, acidic, poisonous gases

they are bonded covalently

Question 49

Are hydrogen halides soluble in water? What do they react with water to produce?

Answer 49

hydrogen halides are very soluble in water

they react with water to produce solutions of acids, such as HCl (a solution of hydrogen chloride in water)

Question 50

What state of matter is HCl at room temperature?

Answer 50

gas

Question 51

What does hydrogen chloride do in water? Is this an alkaline or acidic solution? Why?

Answer 51

hydrogen chloride dissociates in water

the Hcl molecules split into H⁺ ions and Cl^- ions - this process is called dissociation

this is an acidic solution because it contains H⁺

Question 52

When hydrochloric acid solution in water is tested with blue litmus paper, what colour does the paper turn?

Answer 52

blue to pink

Question 53

What does hydrogen chloride do in methy;benzene? Is this an acidic solution? Why?

Answer 53

HCl doesn’t dissociate into H⁺ and Cl^- ions when disolved in organic solvents like methylbenzene

this means there are no H⁺ ions so produced so it is not acidic

Question 54

When hydrogen chloride solution in methylbenzene is tested with blue litmus paper, what colour does the paper turn? What happens if there is any moisture on the paper or in the bottle

Answer 54

the blue litmus paper stays blue

but if there is any moisture on the paper or in the bottle then the HCl can dissociate and it will behave like an acid again

Question 55

What do halogens form with metals?

Answer 55

ionic salts

Question 56

What do halogens form with non-metals?

Answer 56

covalent compounds

Question 57

Halogens are oxidising/reducing agents with oxidising/reducing ability decreasing down the Group

Answer 57

Halogens are oxidising agents with oxidising ability decreasing down the Group

Question 58

What are two uses of halogens in general? What is a use of chlorine? What is a use of iodine?

Answer 58

toothpaste

non-stick coating on drying pans

chlrine kills bacteria - used in bleach and swimming pools

iodine is used as an antiseptic to prevent cuts from being infected

Question 59

Transition metals are typically metallic/non-metallic elements

They are good/poor conductors of heat and electricity

They are workable/not workable, strong/weak, and mostly with high/low densities

With the exception of liquid mercury, Hg, they have high/low melting points

Answer 59

(they are the orange)

Transition metals are typically metallic elements

They are good conductors of heat and electricity

They are workable, strong, and mostly with high densities

With the exception of liquid mercury, Hg, they have high melting points

Question 60

Transition metals are much more/less reactive than the metals in Group 1 and 2, so they do/don’t react as rapidly with air or water

Answer 60

(they are the orange)

Transition metals are much less reactive than the metals in Group 1 and 2, so they don’t react as rapidly with air or water

Question 61

Transition metals form coloured/colourless compounds

Answer 61

Transition metals form coloured ​compounds

Question 62

What are the uses of transition metals?

Answer 62

they are often useful catalsysts:

iron in the manufacture of ammonia (Haber process)

vanadium (V) oxide in the manufacture of sulphuric acid (Contact process)

Question 63

More reactitve halogens … less reactive halogens - they take part in … reaction

Answer 63

More reactitve halogens displacement less reactive halogens - they take part in displacement reaction

Question 64

What happens in the reaction of chlorine water, Cl_{2 (aq)} , with potassium chloride solution, KCl _(aq)? Why?

Answer 64

no reaction

chloride cannot displace chlorine

Question 65

What happens in the reaction of chlorine water, Cl_{2 (aq)} , with potassium bromide solution, KBr _(aq)? Why?

Answer 65

orange solution (Br₂) is formed

the chlorine displaced the bromide because it is more reactive than bromide

Question 66

What happens in the reaction of chlorine water, Cl_{2 (aq)} , with potassium bromide solution, KI _(aq)? Why?

Answer 66

brown solution (I₂) is formed

chlorine displaces the iodide because it is more reactive than iodide

Question 67

What happens in the reaction of chlorine water, Br_{2 (aq)} , with potassium bromide solution, KCl _(aq)? Why?

Answer 67

no reaction

bromine cannot displace chloride because chloride is more reactive than bromine

Question 68

What happens in the reaction of chlorine water, Br_{2 (aq)} , with potassium bromide solution, KBr _(aq)? Why?

Answer 68

no reaction

bromine cannot displace bromide

Question 69

What happens in the reaction of chlorine water, Br_{2 (aq)} , with potassium bromide solution, KI _(aq)? Why?

Answer 69

brown solution (I₂) is formed

bromine displaces the iodide because it is more reactive than iodide

Question 70

What happens in the reaction of iodine water, I_{2 (aq)} , with potassium chloride solution, potassium bromide solution and potassium iodide?

Answer 70

no reaction

chloride and bromide are more reactive than iodine so the iodine cannot displace them

iodine cannot displace iodide

Question 71

What is the equation for the reaction of chlorine water with potassium iodide solution? What type of reaction is this? What is happening to the electrons in this reaction?

Answer 71

this is a displacement reaction:

Cl_{2 (aq)} + 2Kl _(aq) → I_{2 (aq)} + 2KCl_{<span> (aq)</span>}

the electrons are passed from the iodine to the chlorine

each chlorine atom in the Cl₂ molecule gains an electron from two negative Cl^- ions

Two iodide ions lose an electron each and them form a neutral I₂ molecule

chlorine is reduced and iodine is oxidised

Question 72

What is the equation for a the reaction of a metal with dilute?

The more reactive the metal, the faster/slower the reaction will go - very reactive metals (e.g. sodium) react …

What is the speed of reaction indicated by?

Answer 72

metal + dilute acid → salt + hydrogen

The more reactive the metal, the faster the reaction will go - very reactive metals (e.g. sodium) react explosively

the speed of reaction is indicated by the rate at which the bubbles of hydrogen are given off

Question 73

How does magnesium react with cold dilute acids?

Answer 73

magnesium reacts vigorously with cold dilute acids and produces loads of bubbles

Question 74

How does aluminium react with cold dilute acids? Why? How does aluminium react with warm dilute acids?

Answer 74

aluminium doesn’t react much with cold dilute acids because it has a protective aluminium oxide layer

but, it reacts vigorously with warm dilute acids and produces a lot of bubbles

Question 75

How do sinz and iron react with cold dilute acids? What happens if you heat them up?

Answer 75

both zinc and iron react slowly with dilute acids but more strongly if you heat them up

Question 76

What is the equation of a metal reacting with steam?

Answer 76

metal + steam → metal oxide + hydrogen

Question 77

As you go down the reactivity series, the reactions with water become more/less vigorous

Answer 77

As you go down the reactivity series, the reactions with water become less ​vigorous

Question 78

Hydrochloric acid will always produce … salts

Sulphuric acid will always produce … salts

Answer 78

Hydrochloric acid will always produce chloride salts (e.g. magnesium chloride)

Sulphuric acid will always produce sulphate salts (e.g. magnesium sulphate)

Question 79

What is the equation for the reaction of a metal reacting with water?

Answer 79

metal + water → metal hydroxide + hydrogen

Question 80

Very reactive metals, like potassium, sodium, lithium and calcium, will react vigorously with …

Less reactive metals, like magnesium, zinc and iron, won’t react much with … but they will react with …

Copper won’t react with either … or …

Answer 80

Very reactive metals, like potassium, sodium, lithium and calcium, will react vigorously with water

Less reactive metals, like magnesium, zinc and iron, won’t react much with water but they will react with steam

Copper won’t react with either water or steam

Question 81

What is the order of the reactivity series?

Answer 81

Question 82

More reactive metals will … a less reactve metal from its oxide. Why?

Answer 82

More reactive metals will displace a less reactve metal from its oxide

this is because it will bond more strongly to the oxygen

Question 83

What is the word and symbol equation for the reaction of iron oxide with aluminium?

Answer 83

iron oxide + aluminium → aluminium oxide + iron

Fe₂O₃ + 2Al → Al₂O₃ + 2Fe

Question 84

More reactive metals will … less reactive metals in a metal salt (such as sopper sulphate, zinc chloride and sodium chloride)

Answer 84

More reactive metals will displace less reactive metals in a metal salt (such as sopper sulphate, zinc chloride and sodium chloride)

Question 85

What is the word and symbol equation for reaction of copper sulphate with iron?

Answer 85

copper sulphate + iron → iron sulphate + copper

CuSO₄ + Fe → FeSO₄ + Cu

Question 86

What happens if a piece of silver metal is put into a solution of copper sulphate? Why?

Answer 86

nothing happens

this is because the more reactive metal (copper) is already in the salt

Question 87

What are three uses of iron and what property does this depend on?

Answer 87

iron is a strong metal

it is used for building construction, car manufacture and wrought iton garden furniture

Question 88

How is iron galvanised?

Answer 88

a coating of zin is sprayed onto the object

Question 89

How do you prevent rusting on ship’s hulls or underground iron pipes?

Answer 89

sacrificial protection: big blocks of zinc can be bolted to the iron

Question 90

How do you prevent rusting on bike chains?

Answer 90

barrier method: oiling/greasing

this is used when moving parts are involved

Question 91

How do you prevent rusting on big and small structures alike?

Answer 91

barrier method: painting/coating with plastic

can be decorative too

Question 92

What is the atmosphere made up of (percentages)?

Answer 92

78% nitrogen

21% oxygen

nearly 1% argon

0.04% carbon dioxide

there can also be a lot of water vapour too

Question 93

What two ways can you investigate the proportion of oxygen in the atmosphere?

Answer 93

using copper

using iron or phosphorus

Question 94

How do you investigate the proportion of oxygen in the atmosphere by using copper? What is the chemical equation for this reaction?

Answer 94

1. when it’s heated, copper reacts with oxygen in the air to make coppe (II) oxide - so the reaction uses up oxygen
2. if you heat an excess of copper in a tube and pass air over it using two syringes, you can use the markers on the syringe to tell how much oxygen has been used up
3. if you start with 100cm³ of air, you’ll end up with 80cm³ when the reaction is finished and the air has cooled. If 20cm³ air has gone then around 20% of the air must be oxyegn

you need to make sure the system is sealed so no extra air can get in and out

chemical equation:

2Cu + O₂ → 2CuO

Question 95

How do you investigate the proportion of oxygen in the atmosphere by using iron or phosphorus?

Answer 95

1. Iron reacts with oxygen in the air to form rust - so iron will remove oxygen from the air
2. To do this experiment, first soak some iron wool in acetic acid (the acid will catalyse the reaction). Then push the wool into a test tube, put your thumb over the end and ivert the tube into a beaker of water
3. Over time, the level of the water in the test tube will rise - this is because iron reacts with oxygen in the air to make iron oxide. The water rises to fill the space the oxygen took up
4. To work out the percentage of air that is oxygen you need to mark the starting and finishing position of the water
5. Then, fill the tube up to each mark with water and pour the contents into a measuring cylinder to find out the volume of air at the start and the end
6. Using the difference between the start and end volumes to work out the percentage of the starting volume that has been used up - it should be about 20%
7. You can do a similar experiment with white phosphorus. White phosphorus smoulders in air to produce phosphorus oxide. Calculate the amount of oxygen in the air in the same was as for iron

Question 96

How do you make oxygen, O₂, in the lab?

Answer 96

1. It is made using hydrogen peroxide (H₂O₂)
2. The hydrogen peroxide will decompose into water and oxygen:

2H₂O_{2 (aq)} → 2H₂O _(l) + O_{2 (g)}

3. this decomposition is really slwo but the rate of reaction can be increased with maganese (IV) oxide catalyst - this speeds up the reaction without being used up itself
4. you can collect the oxygen that’s produced over water or by using a gas syringe

Question 97

When making oxygen, O₂, in the lab, how do you collect the oxygen over water?

Answer 97

you can use a delivery tube to bubble the gas into an upsdie down measuring cylinder or gas jar filled with water

Question 98

When making oxygen, O₂, in the lab, how do you collect the oxygen by using a gas syringe?

Answer 98

you can use a gas syringe to collect pretty much any gas, including oxygen

Question 99

Oxides can have either … or … character

Answer 99

Oxides can have either acidic or basic character

Question 100

Magnesium burns with a … flame in air and … that is formed is magnesium oxide

The equation for this is: …

Magnesium oxide is slightly … when it’s dissolved in water

Answer 100

Magnesium burns with a bright white flame in air and white powder that is formed is magnesium oxide

The equation for this is: 2Mg _(s) + O_{2 (g)} → 2MgO _(s)

Magnesium oxide is slightly alkaline when it’s dissolved in water

Question 101

Carbon will burn in air if it’s …

It has an … flame and it produces …

The equation for this is: …

Carbon dioxide is slightly … when it’s dissolved in water

Answer 101

Carbon will burn in air if it’s very strongly heated

It has an orangey/yellowy flame and it produces carbon dioxide

The equation for this is: C _(s) + O_{2 (g)} → CO_{2 (g)}

Carbon dioxide is slightly acidic when it’s dissolved in water

Question 102

Sulphur burns in air or oxygen with a … flame and produces …

The equation for this is: …

Sulphur dioxide is … when it’s dissolved in water

Answer 102

Sulphur burns in air or oxygen with a pale blue flame and produces sulphur dioxide

The equation for this is: S _(s) + O_{2 (g)} → SO_{2 (g)}

Sulphur dioxide is acidic when it’s dissolved in water

Question 103

How can you collect gases in a test tube?

Answer 103

upward/ downward delivery

1. the delivery tube is fed directly into a test tube either upwards of downwards
2. use upward delivery to collect ‘lighter than air’ gases (e.g. H₂)
3. use downward delivery to collect ‘heavier than air’ gases (e.g. CO₂, Cl₂)

Question 104

What two ways can you produce carbon dioxide?

Answer 104

reacting dilute hydrochloric acid with calcium carbonate

thermal decomposition of metal carbonates

Question 105

How do you produce carbon dioxide by reacting dilute hydrochloric acid with calcium carbonate?

Answer 105

1. the calcium carbonate (marble chips) is put in the bottom of a sflask and dilute hydrochloric acid is added
2. dilute HCl reacts with the calcium carbonate to produce calcium chloride, water and carbon dioxide gas:

hydrochloric acid + calcium carbonate → calcium chloride + water + carbon dioxide

2HCl _(aq) + CaCO_{3 (s)} → CaCl_{2 (aq)} + H₂O _(l) + CO_{2 (g)}

3. the carbon dioxide gas is collected in a gas syringe or using downward delivery

Question 106

How do you produce carbon dioxide by the thermal decomposition of metal carbonates?

Answer 106

1. heat a metal carbonate (thermal decomposition)
2. copper (II) carbonate is a green powder that will easily decompose to form carbon dioxide and copper (II) ocide when you heat it:

copper (II) carbonate → copper oxide + carbon dioxide

CuCO_{3 (s)} → CuO _(s) + CO_{2 (g)}

5. to do this experiment, heat copper (II) carbonate then collect the gas that’s given off using the downward delivery method

Question 107

What is thermal decomposition?

Answer 107

when a substance breaks down into simpler substances when heates

Question 108

What are two uses of carbon dioxide?

Answer 108

fizzy drinks

fire extinguishers

Question 109

Expalin the role of carbon dioxide in fizzy drinks

Answer 109

CO₂ is used in carbonated drinks to make them fiz

CO₂ is slightly soluble in water and dissolves into the drinks when under pressure - this produces a slightly acidic solution due to the formation of carbonic acid:

carbon dioxide + water → carbonic acid

CO_{2 (g)} + H₂O _(l) → H₂CO_{3 (aq)}

when you open the bottle the bubb;es are the CO₂ excaping - if you leave the drink out long enough it will go flat because all the CO₂ escapes

Question 110

Expalin the role of carbon dioxide in fire extinguishers

Answer 110

carbon dioixide is used in fire extinguishers

CO₂ is more dense than air - so its sinks onto the flame sand stops the oxygen the fire needs getting to it

carbon dioxide fire extinguishers are used when water extinguishers aren’t safe, for example when putting out electrical fires

Question 111

The temperature of the Earth is a balance between … and …

Answer 111

The temperature of the Earth is a balance between the heat it gets from the sun and the heat it radiates back out into space

Question 112

Gases in the atmosphere such as (name three) … naturally act like …

They are often called ‘…’

What do they do?

Answer 112

Gases in the atmosphere like carbon dioxide, methane and water vapour naturally act like an insulating layer

They are often called ‘greenhouse gases’

They absorb most of the heat that would normallly be radiated out into space, and re-radiate it in all directions - inclusing back towards the earth

Question 113

… activity affects the amount of carbon dioxide in the atmosphere - examples include:

1. …
2. …

Answer 113

human activity affects the amount of carbon dioxide in the atmosphere - examples include:

1. deforestation: fewer tress means less CO₂ is removed from the atmosphere via photosynthesis
2. burning fossil fuels: carbon that was ‘locked up’ in these fuels is being released as CO₂

Question 114

The concentration of carbon dioxide over the last 200 years has increased/decreased. Why?

Answer 114

The concentration of carbon dioxide over the last 200 years has increased

CO₂ is being released into the air faster than it’s being removed

Question 115

What is the increase in carbon dioxide linked to?

Answer 115

climate change which causes:

the average temperature of the Earth is increasing (global warming)

changing rainfall patterns

severe flooding due to the polar ice caps melting and sea level rise