Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Revision > Chemistry > Flashcards

Chemistry Flashcards

1
Q

What happens to the electrons of metallic bonding

A

The electrons in the outershelll are delocalised

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

What is metallic bonding

A

Strong forces of electrostatic attraction between positive metal ions and the shared negative electrons

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

What does equilibrium mean

A

when both reactions are happening so they affectively cancel each other out

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

What is a reversible reaction

A

a reversible reaction is when the products of the reaction can be used to create the reactants.

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

What is Potable water

A

Water that is safe to drink

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

Name the first 10 alkanes in order

A

methane
ethane
propane
butane
Pentane
Hexane
Heptane
Octane
Nonane
Decane

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

What are hydrocarbons

A

Compounds that are made up of the elements hydrogen and carbon only

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

What is the general formula for an alkane

A

CnH2n+2

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

What bonds are Alkanes held together by

A

single bonds

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

What qualities do long chain hydrocarbons have

A

they have high melting points due to strong inter-molecular forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What qualities do short chain hydrocarbons have

A

they have low melting points due to weak intermolecular forces

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

How is crude oil is processed

A

crude oil is separated using a technique called fractional distillation

The equipment used to separate crude oil is a fractional column

the column is hot at the bottom and cold at the top

this means that short chain hydrocarbons evaporate at the bottom and then condense back into liquid at the top

while long chain hydro carbons are left at the bottom

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

What is Cracking

A

an example of thermal decomposition where long chain hydrocarbons are broken down into smaller ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the products of cracking a long chain hydrocarbon

A

a short chain alkane and an alkene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are Alkenes

A

a different form of hydrocarbons that is double bonded

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

What is the formula for alkenes

A

CnH2n

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

What are alkenes used for

A

Alkenes are used to make polymers such as polyethene and polypropene

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

What is polyethene used for

A

plastic bags
bottles
dustbins

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

What is polypropene used for

A

it is used to make tough plastics

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

What happens when an alkane is added to bromine

A

it doesn’t change colour.

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

Why does Bromine not change colour when an alkane is added to it

A

Alkanes are saturated hydrocarbons so they don’t have double bonds that can be broken to accept bromine molecules

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

What happens when an Alkene is added to bromine

A

The bromine goes colourless

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

Why does bromine go colourless when an alkene is added to it

A

Alkenes are an unsaturated hydrocarbon so they have double bonds which can be broken to accept the bromine molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What properties do Short-chain hydrocarbons have

A

Less flammable compared to long chain molecules
It easily flows
has a low boiling point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What properties do long-chain hydro-carbons have
more flammable compared to short chain viscous high boiling point
26
What is the chemical formula for photosynthesis
6CO2 + 6H2O > C6H12O6 + 6O2
27
How did Carbon dioxide levels decrease during the early atmosphere
Water vapour condensed into oceans and seas Carbon dioxide from the early atmosphere dissolved into the oceans and seas thus decreasing the amount of carbon dioxide in the atmosphere
28
What is the greenhouse effect
the process in which greenhouse gases trap heat from the sun and reflect it back onto the Earth
29
What is causing the Greenhouse effect to be stronger
As we burn fossil fuels green house gases such as carbon dioxide are released into that atmosphere which causes the green house effect to be stronger
30
What are some examples of green house gases
Methane Water vapour Carbon dioxide
31
How is acid rain caused
When sulphur dioxide is dissolved in rainwater it causes it to be more acidic thus causing acid rain
32
What are some examples of atmospheric pollutants
carbon monoxide, lead, nitrogen oxides particle pollution sulphur oxides.
33
What is the Haber process
the process which allowed the synthetic production of fertilisers
34
How is wastewater treated
Step1: it is screened for any large debris such as sticks and stones Step2: it is put into a settlement tank so all heavier solids sink to the bottom step3:the waste water(effluent) is transferred to another tank where all the organic matter undergoes aerobic digestion step4: the water though not safe for consumption can be released back into the environment
35
What are the advantages of recycling
Save finite resources save energy greenhouse gases shall reduce
36
What are the disadvantages of recycling
recycling items takes fuel and energy materials such as metals can be difficult to sort and in turn recycle without expending a lot of energy
37
What is Phytomining
The process in wich plants are used to extract metal compounds from the ground
38
What is bioleaching
the process in which bacteria are used to extract metals from the ground
39
How is copper processed in bioleaching
bacteria are used to extract copper ions from low grade copper ores. During this process, bacteria convert copper compounds within ores into solution. These copper compound solutions are called the leachate The copper in the leachate goes under a displacement reaction with iron
40
How are the metals in phytomining processed
the metal compounds build up in the leaves of the plant the plants leaves are dried then turned into ash ash dissolved in either hydrochloric or sulphuric acid and then displaced with iron using electrolysis
41
What are the stages of the Life cycle assessment
stage 1: extracting raw materials needed to make product and then processing them Stage 2: manufacturing and packaging product Stage 3: use of the product during its lifetime stage 4: disposal at the end of a products life
42
What is Le chateliers principle
That if you change the conditions of a reversible reaction at equilibrium the system will try and counteract the change
43
In accordance with Le Chateliers principle what happens if you change the temperature
If you decrease the temperature the equilibrium will move in the exothermic direction to increase the temperature If you increase the temperature the equilibrium will move in the endothermic direction of the reaction producing less heat
44
In accordance with Le Chateliers principle what happens if you change the pressure
Changing pressure only affects equilibriums with gases If you increase the pressure the equilibrium will decrease the pressure by moving to an area with few gas molecules/ producing gas that has less molecules If you decrease the pressure the equilibrium will increase the pressure by moving to an area with a high amount of gas molecules/ producing gas that has more molecules
45
In accordance with Le Chateliers principle what happens if you change the concentration
If you increase concentration of reactants more products are produced if you decrease concentration of reactants the amount of products will also decrease
46
What is the formula for methane
CH4
47
What is the formula for Ethane
C2H6
48
What is the formula for Propane
C3H8
49
What is the formula for Butane
C4H10
50
In chemistry what is a pure substance
A substance that only contains one element or compound throughout
51
What does the boiling/melting point of a substance tell about a substance
A chemically pure substance will melt or boil at a specific temperature impurities in sample will decrease the melting point and increase the melting range impurities in sample will increase the boiling point
52
What is the test for Chlorine
Chlorine bleaches damp litmus paper if you use blue litmus paper it may turn red as the chlorine solution is acidic
53
What is the test for oxygen
if you put glowing splint in test tube filled with oxygen the oxygen will relight the splint
54
What is the test for carbon dioxide
Bubbling carbon dioxide into a solution of calcium hydroxide (lime water) will cause it to go cloudy
55
What is the test for hydrogen
if you hold a burning splint over a test tube filled with hydrogen a squeaky pop will be heard
56
What is the mobile phase of Chromatography
Where the molecules can move. This is always a liquid or gas
57
What is the stationary phase of chromatography
Where the molecules cant move. This can be a solid or a really thick liquid
58
What is the stationary phase of chromatography
Where the molecules cant move. This can be a solid or a really thick liquid
59
What factors determine how quickly a chemical moves in chromatography
How quickly a chemical moves depends on which phase it spends the most time in for example if a chemical spends more time in the mobile phase then it will move further through the stationary phase.
60
What are the steps of chromatography
Draw a line near the bottom of the filter paper with a pencil add a spot of ink on the line and place the sheet in a beaker of solvent e.g. water The solvent used depends on what's being tested. some compounds dissolve well in water some don't so in turn we may have to use ethanol Make sure ink isn't touching solvent Place a lid on top of beaker to stop solvent from evaporating The solvent seeps up the paper, carrying the ink with it As the ink moves up the dyes in the ink will separate forming spots along the sheet representing each dye insoluble dyes will stay at the base line when the solvent reaches top of filter paper take paper out and leave it to dry The end result is called a chromatogram
61
What is the RF value dependent on
The type of solvent used
62
How did Volcanic activity contribute to the growth of our atmosphere
Volcanic activity released nitrogen and carbon dioxide as well as water vapor while also releasing small amounts of methane and ammonia
63
How did the oceans, algae and green plants contribute to our atmosphere
Lots of carbon dioxide was dissolved into the oceans and after a series of reactions formed carbonate precipitates that formed the sediments on the seabed Algae and green plants absorbed CO2 to carry out photosynthesis
64
How did algae and green plants contribute to our atmosphere
They carried out photosynthesis decreasing the amount of CO2 and increasing the amount of oxygen in the atmosphere.
65
How do greenhouse gases induce climate change
Green house gases don't absorb the short wave radiation from the sun but instead the long wave radiation that gets reflected back off the earth They green house gases then reflect that long wave radiation back onto Earth constantly Since long wave radiation is thermal radiation it will heat up the Earth when its reflected back onto Earth Thus global warming
66
What are the negatives of bioleaching
it produces toxic substances, including sulfuric acid, which damage the environment.

Revision (18 decks)

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