Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GCSE > Chemistry- Core > Flashcards

Chemistry- Core Flashcards

(76 cards)

Start Studying
0
Q

The benefits and costs of emulsion

A 
\+looks nice 
\+low in fat
\+good texture 
\+thicker 
- allergies, uses egg yolks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

How do emulsions work?

A

Hydrophilic latches on to water molecules
Hydrophobic latches on to oil molecules
Other oil droplets are repelled by the hydrophilic part while the water molecules latch on so the emulsion does not spread out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe an ionic bond

A

Its between metal and non-metal atoms

Metal loses one electron and forms a positive ion whereas the non-metal gains electrons and forms a negative ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the negative effects of quarrying?

A 
Ruins landscape 
Noise pollution 
Burns fossil fuels 
Dust effects breathing 
Air pollution from trucks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the positive effects of quarrying?

A 
Its used to make houses and roads 
Restores land once finished 
Boosts local economy 
Neutralises acidic soil and rivers 
Neutralises sulfur dioxide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is hydrogenation?

A

The process of hardening vegetable oils to increase there boiling temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the process of hydrogenation

A

Reacting vegetable oils with hydrogen over a nickel catalyst at 60degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is ethanol used as an alternative fuel and what are the pros and cons?

A

-fermentation of plants
+ carbon neutral
- engine has to be converted
-have to grow instead of food raising food prices

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where is hydrogen from (alternative fuel) and what are the pros and cons?

A

-water and electrolysis
+ clean
-expensive
-hard to store

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is polymerisation? What alter the polymers properties?

A

Polymerisation is when the double bonds in alkenes open to form single bonds thus joining molecules together
- what its made from, the temperature and the pressure during polymerisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why are vegetable oils used in cooking?

A 
Provide energy
Contain nutrients such as vitamin E
Contain essential fatty acids 
Higher boiling points so can cook quicker at higher temperatures 
Different flavours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does the test for carbon dioxide work?

A

Limewater is a solution of calcium hydroxide and is alkaline so when it reacts with carbon dioxide which is a weak acid it forms tiny solid particles of insoluble calcium carbonate (precipitate) this proves that there is carbon dioxide in the solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens when an element from group 1 reacts with water?

A

An metal hydroxide and hydrogen are formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is ethanol produced from sugar?

A 
Sugar=ethanol+carbon dioxide (yeast)
The enzymes in the yeast break down the sugar to form ethanol and carbon dioxide this is called fermentation
\+sugar is renewable 
\+cheap
\+low temperatures
-not highly concentrated 
- has to be distilled and purified
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is ethanol produced from ethene?

A 
The ethene is passed over a catalyst with steam this is called hydration
\+cheap
\+reversible and continuous
\+no waste 
- ethene is produced from crude oil 
-high energy and pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name environmental problems

A

Carbon monoxide - incomplete combustion red blood cells pick it uk and carry it to cells instead of oxygen it is poisonous
Nitrogen oxides - high temps acid rain
Sulfur dioxide- acid rain damages buildings, limestone statues and makes lakes acidic
Carbon dioxide - pollution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is cracking?

A

The process of splitting up longer chain molecules into smaller more useful molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does cracking work?

A

The long chained molecules are vaporised and passed over powdered aluminium oxide (catalyst) at 400-700 degrees the molecules split on the surface of the catalyst
This is a THERMAL DECOMPOSITION reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which hydrocarbon is saturated, alkenes or alkanes?

A

Alkanes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why doesn’t methene exist

A

Methane only has one carbon atom so couldn’t be double bonded

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do you make cement?

A

Powdered limestone is heated in a kiln with powdered clay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How do you make mortar?

A

Cement +sand + water = mortar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do you make concrete?

A

Cement + sand + aggregate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why would decane have a have a higher boiling point that propane?

A

Long chain hydrocarbons have more bonds which take more energy to break apart so long chain hydrocarbons have higher boiling points

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Why isn't pure iron useful?
Regular arrangement of atoms which have layers that easily slide over one another this makes it too soft and too bendy
25
Why is cast iron difficult to use?
Its 4% carbon so is brittle and hard as well as difficult to be compressed - it can be moulded when molten
26
What is low carbon steel used for?
Easily shaped | Car bodies
27
What is high carbon steel used for?
Hard Inflexible Blades and tools
28
What is stainless steel used for?
Corrosion resistant | Cutlery
29
How do you convert cast iron to steel?
1. Put it in a blast furnace 2. Blow oxygen into the furnace 3. This reacts with molten iron 4. Produces carbon dioxide can carbon monoxide and steel
30
What is a metal ore?
A rock that has enough metal in it to make it economically worth extracting
31
What is reduction?
Reduction is the removal of a metal from an ore by using carbon as long as the metal is below carbon in the reactivity series
32
What is smelting?
Heating a metal ore in order to extract its metal
33
Why do you have to use electrolysis to purify copper after it has been smelted?
The copper does not conduct electricity after it has been smelted as its impure
34
How does electrolysis work?
1. The electrons go from the metal atoms to the anode (positive electrode) and turn to postively charged ions 2. Ions then go to the cathode (negative electrode) and turn back to metal atoms 3. The impurities are dropped at the anode as sludge
35
How does bio-leaching work?
Uses bacteria to separate the copper from the copper sulfide Bacteria gets energy from the bind separating out the copper from the ore Leachate is the product which contains copper which has to be filtered out
36
What are the impact of extracting metals?
- noise - mining shafts are dangerous - pollution - scares landscape + jobs + local economy + useful products made
37
How does displacement work?
Put a more reactive metal with another metal and it will displace this is because the metal bonds more strongly to the non-metal pushing it out
38
How does phytomining work?
Plants are grown in soil which contains copper Plants take copper in but cant use it so they store it in the leaves Plants are harvested, dried, burned Copper is then collected from the ash
39
Name the properties of copper
Conductor of electricity Doesn't react with water Hard Strong
40
Name the properties of aluminium?
Corrosion resistant Low density Not strong Forms strong hard alloys
41
Name the properties of titanium
Corrosion resistant Low density Very strong
42
How do you extract aluminium?
Electrolysis - molten aluminium oxide at high temperatures
43
How do you extract titanium?
Displacement - with sodium or magnesium Have to convert to chloride Then distill and purify
44
Why would you not use carbon to displace and extract titanium?
Reacts with the titanium making it brittle
45
What was Wenger's theory?
All continents came from a massive continent called Pangea They all fit like jigsaw pieces Matching layers and rocks Similar fossils that were in the wrong areas
46
Describe the earth structure
Crust: 5-50km very thin made up of tectonic plates Mantle: starts at core 3000km down acts like a solid but is very hot Core: radius of 3500km nickel and iron Outer: liquid Inner: solid
47
How are mountains and volcanos formed?
The tectonic plates collide pushing each other up
48
How did the early atmosphere evolve?
- earth cooled and thin layer of crust formed - volcanoes erupted water vapour, ammonia, methane and lots of co2 - water vapour condensed into oceans - plants and algae liked co2 so grew all over earth - took in co2 and produced O2 using photosynthesis - CO2 dissolved into ocean and locked up in sedimentary rocks - O2 build up, killed early organisms - created ozone layer blocked harmful sun rays and allowed complex organisms to form
49
Can we predict earthquakes and volcanic eruptions?
No, but there are usually signs such as ground bulges and mini earthquakes near the volcano Earthquakes rocks get hotter
50
How does fractional distill air work?
Air is filtered Cooled to -200 degrees and becomes a liquid Water vapour condenses and is removed Liquid enters column and is heated slowly Separated air CO2 and argon come out together so go to another column
51
What is the primordial soup theory?
Earth was rich with nitrogen, hydrogen, ammonia and methane, lightening struck and caused a chemical reaction between the gases forming amino acids which were collected in a body of water, these combined to form organic matter and living organisms
52
What are the advantages if using limestone as a building material?
Widely available, cheap, concrete can be poured into moulds, fire resistant, don't rot
53
What is a biofuel and give an example?
Biofuels are fuels made from plant and animal matter | E.g. Ethanol
54
Describe a covalent bond
Two or more non-metal atoms each atom shares an electron with the other
55
The total masse before ...
Equal the total mass after
56
When the non-metals react with metals what are the particles called?
Ions
57
When the non-metals react with the non-metals what are the particles called?
Molecules
58
What are groups?
Elements with similar properties
59
Give the properties of an ionic bond
Strong due to opposing charges
60
What is the atomic number?
The number of protons
61
How do you work out the number of neutrons?
Mass number - atomic number
62
Why is there no overall charge on an atom?
Equal amount of protons and electrons so they cancel each other out Neutrons are neutral Protons are positive Electrons are negative
63
Name the good properties of limestone
Cheap, hardwearing, doesn't rot or corrode
64
Describe how a rotary kiln works?
``` Fill with crushed limestone Heat using hot air CaO comes out bottom Waste gas leaves top Rotated so limestone is mixed well ```
65
Give limestone cycle equations
CaCO3 > CaO + CO2 CaO + H2O > Ca(OH)2 Ca(OH)2 + CO2 > CaCO3 + H2O
66
What was wrong with the miler-Urey experiment?
- only 11 amino acids - not correct ones - not as many made - no proof of lightening
67
Give formula for alkane
CnH2n+2
68
Give formula for alkene
CnH2n
69
What happens to bromine when it reacts with an unsaturated hydrocarbon?
Reacts and goes colourless
70
What happens when bromine water react with a saturated hydrocarbon?
No reaction and it stays orange
71
Describe fractional distillation
1. Crude oil goes through pipe as vapour 2. Hot at bottom and cool at top 3. Oil remains as a liquid this goes out the bottom 4. Vaporised oil rises up the column and at various fractions condense when they reach there boiling points 5. There collected at the different points
72
What is the product of cracking?
Alkanes and alkenes
73
How do you reduce SO2
Stop burning fossil fuels Acid gas scrubber Catalytic converter
74
Why do some oils need to be distilled after extraction?
To remove water Solvents Impurities
75
What does cracking do?
Open double bonds and increase melting points

GCSE (55 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions