wrong questions

Question 1

describe how ethanol is produced from sugar solution

Answer 1

fermentation
add yeast
anaerobic conditions
warm

Question 2

gas produced when sodium is added to athanol

Answer 2

hydrogen

Question 3

how has co2 decreased and oxygen increased

Answer 3

volcanic activity released water vapour
the water vapour condensed to form oceans
carbon dioxide dissolved in oceans
carbonates produce sediments
carbon locked up in sedimentary rocks

algae and plants evolved/appeared
algae plants absorbed carbon dioxide by photosynthesis
which also released o2

carbon locked up in fossil fuels 1

Question 4

two effects of atmospheric pollution reduced by using cataliytic converters (reduce the amount of pollutants released)

Answer 4

acid rain
respiratory problemes
carbon monoxide
global dimming, smog

Question 5

sodium thiosulfate reacts with dilute hydrochloric acid
plan an investigation to show how the concentration of the sodium thiosulfate solution affects the rate of reaction with dilute hydrochloric acid

Answer 5

measure (indicated) volume of sodium thiosulfate place sodium thiosulfate in (conical) flask
• measure (indicated) volume of hydrochloric acid
• place on cross
swirl
start stopwatch
meature time for cross to become no longer visible
measure time for fixed volume of gas to be produced
• repeat and find mean
repeat for different concentrations of sodium thiosulfate

control variables
• concentration of hydrochloric acid volume of hydrochloric acid
• (otal) volume of sodium thioslate solution

Question 6

limewater is an aqueous solution of

Answer 6

calcium hydroxide

Question 7

why increase in world pop may have caused the increase in conc of CO2 in atmosphere

Answer 7

increased pop so more energy required
so more fossil fuels burned

Question 8

bioleaching

Answer 8

the us of bacteria
to produce leachate solutions that contain copper compounds

Question 9

name a compound needed to produce nitric acid

Answer 9

ammonia

Question 10

why are larger hydrocarbons more viscous

Answer 10

as molecular size increases, viscosity increases
and larger hydrocarbons have larger molecules

Question 11

what happens to effluent and sludge

Answer 11

anaerobic digestion of sludge

aerobic biological treatment of effluent

Question 12

pure water

Answer 12

water in its natural state

Question 13

where are the reactants of haber process from

Answer 13

nitrogen—atmosphere
hydrogen—natural gas

Question 14

haber process conditions why

Answer 14

rate
• higher temperature gives higher rate because of more frequent collisions
• higher temperature gives higher rate because more particles have the activation energy
• higher pressure gives higher rate because of more frequent collisions
Use of catalyst gives higher rate because the activation energy is lowered

equilibrium
• higher temperature shifts the position of equilibrium to the left because reaction is exothermic
• higher pressure shifts the position of equilibrium to the right because more molecules on left-hand side
use of catalyst has no effect on the position of equilibrium

other factors
• higher temperature (than 450°C) uses more energy so increases costs
• higher pressure (than 200 atmospheres) uses more energy so increases costs
• higher pressure (than 200 atmospheres) requires stronger reaction vessels so increases costs
• use of a catalyst reduces energy costs

compromise
• the temperature chosen is a compromise between rate of reaction and position of equilibrium
the temperature chosen is a compromise between rate and cost
•the pressure chosen is a compromise between yield / rate and

Question 15

aluminium excess NaOH

Answer 15

precipate is soluble in excess sodium hydroxide
so it redissolves

Question 16

how greenhouse gas keeps earth warm

Answer 16

greenhouse gases allows shorter wavelength radiation to pass through from sun

]which is reemitted from the surfaces as longer wavelength radiation

which is absorbed by greenhouse gases in the atmosphere

Question 17

CO2 bad

Answer 17

greenhouse gas
surface temp increases
so global warming
so climate change
so polar ice caps melt
so sea levels in crease
so flooding
so extreme weather events
so reduction in biodiversity
so famine/drought

Question 18

sulfure dioxide bad

Answer 18

acid rain
so damage to buildings/statures
so damage to trees
so damage to aquatic animals
so respiratory problems in humans

Question 19

carbon/soot bad

Answer 19

particulates
cause global dimming
so respiratory problems in humans

Question 20

why is recylcing ores better

Answer 20

recycling conserves ores
uses less energy than the energy used to make new
recycling reduces waste in landfill

Question 21

phytomining

Answer 21

grow plants on land containing copper ores
plants are burnt to produce ash
ash dissolved in acid to produce a solution of a copper compound
electrolysis of solution to get copper

Question 22

why oxides of nitrogen bad

Answer 22

more acid rain
more respiratory problems

Question 23

lcas energy

Answer 23

energy may be from fossil fuels
which causes pollution (specified)

Question 24

why recyucling good

Answer 24

recycling conserves finite resources
uses less energy than making new products
reduce use of landfill

Question 25

why reusable good

Answer 25

conserves natural resources replaced less often

Question 26

why heavier products bad in lcas

Answer 26

takes more energy to transport harder to transport

Question 27

mining bad

Answer 27

pollutes environment need to use energy to process the mined raw materials

Question 28

why aluminium doesn’t need protection from corrosion

Answer 28

aluminium has oxide coating so contact between aluminium and water/air/oxygen is prevented

Question 29

why is higher pressure not used to reacitions

Answer 29

yield already high more energy required risk of explosion is increased

Question 30

why thermosetting polymers don’t melt when heated

Answer 30

have strong crosslinkes between chains so too much energy need to overcome the cross links

Question 31

explain how the different dyes are separated by paper chromatography

Answer 31

solvent moves through paper different dyes have different solubilities in solvent and different attractions for the paper and so are carried different distances up the paper

Question 32

why flame test cannot be used to indentify two metal ions

Answer 32

colours mix as there will be two different colours

Question 33

why does rate of reaction decrease

Answer 33

acid particles used up so concentration decreases so less frequent collisions

Question 34

how is potable water produced from different sources of fresh water

Answer 34

choose an appropriate source of fresh water such as rivers, streams, lakes, boreholes pass water through filter beds, which removes undissolved solids sterilise using chlorine/ozone/UV which destroys harmful microbes

Question 35

difference between ethane and ethene (reactions)

Answer 35

both react with O2 in complete combustion reactions to produce water and carbon dioxide both react with oxygen in incomplete combustion reactions to produce water and carbon monoxide incomplete combustion is more likely with ethen bromine water ethene is more reactive ethen can react with hydrogen to produce ethane ethene can react with water to produce ethanol ethene can polymerise to produce poly(ethene)

Question 36

why reducing the amount of sulfur in fossil fuels reduces the erosion of limestone

Answer 36

sulfur reacts with O2 to form sulfur dioxide so less sulfur dioxide emitted less acid rain so less limestone reacts with acid rain

Question 37

potable water (fresh water)

Answer 37

pass water through filter beds to remove solids use chlorine/ozone/UV to sterilise water to destroy microbe

Question 38

waste water treatment

Answer 38

screening using a metal grid to remove solids to remove grid sedimentation to produce sewage sludge and effluent anaerobic digestion of sewage sludge aerobic biological treatment of effluent