C1 - Exam Mistakes

Question 0

Compounds formed when non-metals react with metals consist of particles called…

Answer 0

Ions

Question 1

Explain why fluorine and chlorine are in the same group in the periodic table. Explain using electronic structures. 2 marks

Answer 1

Electronic structure of fluorine is 2,7 and chlorine is 2,8,7

So they are in the same group because the have the same number of electrons in their outer shell

Question 2

Compounds formed when only non-metals react consist of particles called…

Answer 2

Molecules

Question 3

Why are there many theories to how life formed on Earth?

Answer 3

Not enough evidence or proof

Life on Earth started billions of years ago

Question 4

What is the problem with cast iron?

Answer 4

Cast iron is brittle

Question 5

State one property that makes aluminium more suitable than copper for overhead cables

Answer 5

Aluminum has a low density

Question 6

Why are vegetable oils important in food?

Answer 6

Provide energy

Question 7

Explain how emulsifier molecules are able to make an emulation. 4 marks

Answer 7

Molecule has a hydrophillic end which is attracted to water

Molecule has hydrophobic end which is attracted to oil

So forms a stable suspension of droplets of oil in water or vice versa

Hydrophilic is the head of the molecule and hydrophobic is tail

Question 8

How is the solid waste yeast removed after fermentation?

Answer 8

It is filtered out

Question 9

How is the ethanol obtained from the solution after fermentation?

Answer 9

Distillation

Question 10

Give 3 advantages of using biodiesel instead of petroleum diesel

Answer 10

Produces less carbon dioxide (less global warming)

Produces no sulphur dioxide (no acid rain)

Conserves the limited amount of petroleum diesel because biodiesel is renewable

Question 11

Give 3 disadvantages of using biodiesel instead of petroleum diesel

Answer 11

Destruction of habitats

More nitrogen oxides released

Uses crops that could be used for food

Question 12

Describe how continental drift happens. 5 marks

Answer 12

Because the Earth’s crust

Is divided into tectonic plates

The heat released from radioactive processes

Causes convection currents

In the mantle that move the tectonic plates

Question 13

When air is distilled, why is carbon dioxide removed before the gases are cooled to -200C?

Answer 13

It forms a solid / freezes

Question 14

Describe the conditions in the cracking reactor

Answer 14

Vapours of hydro carbon passed over aluminum oxide catalyst

Hydro carbon mixed with steam at high temperatures

Question 15

Why mustn’t air enter the cracking reactor?

Answer 15

Oxygen could react with hydrocarbons

Question 16

How does polymerisation happen?

Answer 16

Many monomers

Form long chain molecules which are polymers

Question 17

Give 3 reasons that copper is extracted from ores containing a very low amount of copper in them

Answer 17

Copper is running out

Copper metal is in demand

Now economical to extract copper from low-grade ores

Question 18

What type of reaction releases energy from a fuel?

Answer 18

Exothermic

Question 19

What is locked up carbon dioxide? 2 marks

Answer 19

Carbon dioxide from the air and Earth’s early atmosphere

Formed sedimentary rocks or fossil fuels

Question 20

Describe how the process of fermentation is done

Answer 20

Sugar is dissolved in water

Yeast is added

Fermentation will then take place naturally

Question 21

How do you cause an emulsifier to make an emulsion and why?

Answer 21

Shake the oil and water mixture

This breaks the oil into tiny droplets

Question 22

How can changes to limewater be used to measure how long it took for car in dioxide to be produced. 2 marks

Answer 22

They could measure the time since heating started to when limewater turns cloudy

Question 23

Why does Iceland have volcanoes?

Answer 23

It is on the BOUNDARY between tectonic plates

Question 24

Why don't we know exactly when a volcano will erupt?

Answer 24

Scientists can't measure what is happening below crust

Question 25

A student said that hardening olive oil will make it healthier. Is this correct and why? 2 marks

Answer 25

No because hydrogen in hydrogenation adds to the in saturated fat Therefore there will be less unsaturated fat

Question 26

What are the conditions for the hydration of ethene to make ethanol?

Answer 26

Presence of catalyst

Question 27

Why does low carbon steel production use oxygen but titanium production use argon? 3 marks

Answer 27

Oxygen is needed to oxidise carbon Argon atmosphere used because it is unreactive Oxygen would react with titanium

Question 28

What effect does having more manufacturing processes for a material have on how good the process is?

Answer 28

More energy needed so the process isn't as good

Question 29

Give 3 advantages of extracting crude oil from Canadian oil sands

Answer 29

It is needed because crude oil is running out can't meet demand Could improve Canada's economy Could provide many jobs for people

Question 30

Give 3 disadvantages of extracting crude oil from Canadian oil sands

Answer 30

Destruction of habitats Crude oil is non-renewable Burning crude oil releases carbon dioxide

Question 31

Give a disadvantage of recycling materials from a ballpoint pen

Answer 31

Cost of separating materials is high

Question 32

Give 2 reasons why alloys are used in the ballpoint pen

Answer 32

Harder than pure metals Corrosion resistant

Question 33

Give 2 reasons why the carbon dioxide in the atmosphere has decreased over millions of years

Answer 33

Photosynthesis Carbon dioxide locked up in sedimentary rock

Question 34

Why do nitrogen oxides form in car engines? 2 marks

Answer 34

Nitrogen and oxygen in air Hot temperature causes then to react

Question 35

What is hydration?

Answer 35

Reaction with water (steam)

Question 36

Suggest 2 reasons why phytomining is used on a certain area of land instead of other methods

Answer 36

Small amount of copper More economical

Question 37

Calcium carbonate is heated and the expected final mass is 2.2g. Give 2 reasons and explain why that might not happen. 4 marks

Answer 37

Calcium carbonate contained impurities (less carbon dioxide produced) Temperature not high enough (calcium carbonate didn't fully decompose)

Question 38

Why didn't scientists in 1915 not accept Wegener's theory?

Answer 38

Couldn't explain why the continents moved