Aqa Chemistry Unit 1

Front 1

Why are current methods of extracting metals expensive?

Back 1

There are lots of stages which require large amounts of energy.

Front 2

How do you make cement?

Back 2

Heating limestone with clay.

Front 3

What do particulates released from the incomplete combustion of fuels cause?

Back 3

Global Dimming

Front 4

What is the Earth's structure?

Back 4

Crust

Mantle

Core

Front 5

What are the advantages of using fermentation to produce ethanol?

Back 5

Carbon Neutral

Renewable

Cheap

Front 6

What are the disadvantages of using fermentation to produce ethanol?

Back 6

Not continuous

You cannot get a concentration of above 15% as the yeast will die.

Front 7

What is the difference between cooking with vegetable oil and boiling?

Back 7

Food has a different taste, texture, cooks quicker and releases more energy.

Front 8

What is the difference between an alkane and an alkene?

Back 8

Alkanes have a single bond between their carbons. This means they are saturated.

Front 9

How do we produce vegetable oils?

Back 9

Crush then press the raw materials then distill the mixture to get rid of impurities.

Front 10

What are the advantages of biofuels?

Back 10

Carbon Neutral

Renewable

Does produce SO2

Front 11

What are the disadvantages of biofuels?

Back 11

They increase food prices

Take up land

Require a large labour force

Production is not continuous

Front 12

How can limestone be used to clean fuel emissions?

Back 12

The calcium reacts with the sulphur to make calcium sulphate which could be used in plasterboard.

Front 13

Why do atoms have no charge?

Back 13

They have an equal amount of protons and electrons.

Front 14

What are the properties of polymers?

Back 14

Strong bonds between atoms, weak intermolecular forces therefore a low melting point.

Front 15

Chemical equation for the thermal decomposition of limestone?

Back 15

Front 16

Chemical equation for calcium oxide plus water?

Back 16

Front 17

Why do we use aluminum for overhead wires instead of copper?

Back 17

It is cheaper to do so and aluminum is lighter.

Front 18

Why don't we use cast iron for pylons?

Back 18

It is brittle and corrodes by rusting.

Front 19

How do emulsifiers work?

Back 19

They have a hydrophobic end which dissolves in oil and a hydrophillic end that dissolves in water which joins the two together.

Front 20

Why is scrap iron used to displace copper from its ore?

Back 20

It is more reactive than copper and cheap to obtain.

Front 21

How do you harden vegetavle oils and what does this process do?

Back 21

You add hydrogen to them with a nickel catalyst at 60°C which increases their melting point making them solid at room temperature so they are more useful in things like spreads, cakes and pastries.

It also makes them more saturated.

Front 22

How do you separate liquids with different boiling points.

Back 22

Evaporate them(distillation)

Front 23

How do you seperate hydrocarbons?

Back 23

Fractional distillation.

Front 24

How do you calculate the mean with an anomalous result?

Back 24

Discount the anomaly in any calculation.

Front 25

What is polymerisation?

Back 25

The joining together of monomers into one large molecule called a polymer.

Front 26

Why was continental drift not accepted by scientists?

Back 26

Insufficient evidence.

Front 27

What is the theory of continetal drift?

Back 27

The idea that Earth's landmasses where once joined together but seperated over millions of years as they were adrift on a liquid core.

Front 28

What conditions are require for cracking?

Back 28

Immense heat and high pressure with no oxygen(this stops combustion)

Front 29

What is cracking?

Back 29

A form of themal decomposition which breaks down large hydrocarbons into smaller, more useful ones.

Front 30

How do you make concrete?

Back 30

Cement, sand and aggregates.

Front 31

What are the advantages of using hydrogen as a fuel?

Back 31

Renewable

Clean

Front 32

What are the disadvantages of using hydrogen as a fuel?

Back 32

It is hard to store

Flammable

Expensive

Front 33

What is an ore?

Back 33

Any rock which contains enough metal to make extraction viable.

Front 34

How was carbon dioxide removed from the atmosphere according to the early Earth theory?

Back 34

Dissolved in water

Trapped in sediments

Photosynthesised in green plants

Front 35

What is the name for iron from a blast furnace?

Back 35

Cast iron

Front 36

Why is cast iron so hard and brittle?

Back 36

It contains impurities.

Front 37

What is the scientific name for the chemical reaction that happens when things burn?

Back 37

Combustion.

Front 38

What three things are needed for something to burn?

Back 38

Fuel

Oxygen

Heat

Front 39

As well as hydrogen and carbon, what element do fossil fuels often have?

Back 39

Sulphur

Front 40

What harmful gas maybe formed instead of CO2 in incomplete combustion?

Back 40

Carbon monoxide.

Front 41

What resource do we get ethene from?

Back 41

Crude oil.

Front 42

What do emulsifiers do to a face cream?

Back 42

They improve the texture, coating ability and appearance of the cream.

Front 43

The method used to dig a metal ore from the ground is called what?

Back 43

Mining

Front 44

After an ore is mined what process removes the metal from its ore?

Back 44

Extraction

Front 45

Certain metals like gold are found as pure metals, why?

Back 45

They are unreactive.

Front 46

Limestone is quarried and used as a main material for making what substances?

Back 46

Cement

Glass

Front 47

What is the scientific term for breaking something down with heat?

Back 47

Thermal decomposition

Front 48

How is limestone made?

Back 48

The remains of sea creatures

Front 49

What are the downsides of quarrying?

Back 49

It destroys habitats

It scar the land

It is expensive

Front 50

Why is calcium oxide stored in dry, argon conditions?

Back 50

It will react easily with water to form calcium hydroxide.

Front 51

When thermally decomposing limestone, why would you get a higher yield than predicted?

Back 51

-The limestone might be impure so not a lot of CO2 will be produced.

-You might not heat it to a high enough temperature so not a lot of CO2 will be given off as it won't fully decompose.

Front 52

Some fruits and seeds are rich in vegetable oils. What other common food type is as well?

Back 52

Nuts

Front 53

If foods are cooked in oil, what happens to their fat content?

Back 53

It increases.

Front 54

Are food cooked in oils thought to be generally better or worse for our health?

Back 54

Worse.

Front 55

For approximately how many years have the proportions of gases in the atmosphere been as they are today?

Back 55

200 million years

Front 56

Name the process that formed the oceans from water vapour in earth's early atmosphere.

Back 56

Condensation

Front 57

What sedimentary rock is made from the shells of dead sea creatures?

Back 57

Limestone

Front 58

Biodegradable things are made from polymers and what else?

Back 58

Cornstarch.

Front 59

Fabrics are often coated in plastics to make them what?

Back 59

Waterproof.

Front 60

Who proposed the theory of continental drift?

Back 60

Wegener

Front 61

What are the earth's crust and upper mantle cracked into?

Back 61

Tectonic plates

Front 62

What causes tectonic plates to move?

Back 62

Convection currents in the earth's liquid mantle.

Front 63

What polymer are most U.K shopping bags made from?

Back 63

Polyethene

Front 64

A polymer that retains its original shape is called a what?

Back 64

Shape memory polymer.

Front 65

What do you add to iron to make steel?

Back 65

Carbon

Front 66

In a fractional distillation column, what process is caused by heating?

Back 66

Evaporation

Front 67

At what temperature are vegetable oils hardened?

Back 67

60°C

Front 68

When talking about alkanes, what does saturated mean?

Back 68

They contain the largest number of hydrogen atoms.

Front 69

What two planets in our solar system do researchers think the early earth's atmosphere was similar to?

Back 69

Mars and Venus

Front 70

Apart from plants, what other organisms photosynthesise?

Back 70

Algae