2022 paper 2 Flashcards
why does poly(butene) be removed from scrap copper wire before copper is recycled
otherwise copper is impure
explain why contents in test tube decreased after heating it
water vapour was produced and escaped from the tube
suggest why the test tube and content were heated until mas didnt change
to get to the end of the reaction as this is the point when its complete
evaluate use of glass and a polymer for milk bottles
extraction: glass bottles require more energy to extract but the polymer is made from crude oil which is a finite resource
manufacturing: glass bottles requre more enrgy to produce and has they have a heavier mass they will require more energy than polymer to transport
Use: Glass bottles can be re used mutliple times however water is needed to wash it after every use
Disposal: both are recyclable so both reduce the fill up of landfills
overall i think polymer is the best material as it has a lower overall energy consumption
explain how fractions are obtained from crude oil
crude oil is heated to vaporise the hydrocarbons. In the fractionating coloumn there is a temperature gradient so the further up the coloumn the cooler it is. The gasses will therefore condense at different levels beacuse of their different boiling points
what conditions are needed for cracking
high temp
catalyst / steam
describe how sewage removes organic matter
First sewage is passed through a screen to remove large debris and grit. then the sewage is put in sedimentation tanks to separate the sewage sludge and effluent. the effluent is digested by aerobic bacteria and the sludge is digested by anaerobic bacteria
why wouldnt filtration work to remove ions
ions will pass through filter paper as they are in the solotion
suggest what is meant by pure if a company says they have pure water
nothing else is added to the water
explain how the ammonia produced is seperated from unreacted nitrogen and hydrogen
the mixture is cooled so that only ammonia liquifies so it can be easily removed
explain why the harbour process is carried out at 450 degress and 200 atm pressure and iron catalyst
a higher temperature increases rate of reaction as particles have more kenetic energy nd so collide with each other more frequently. however as the reaction is exothermic increasing temperature means equilibrium shifts left so temperature is a compromise between yield and rate of reaction. a higher pressure means the equillibrium will shift to right however if pressure is too high then the cost increases and it could become dangerous to carry out so pressure is a compromise between yeild and cost. An iron catalust provides an alternate pathway for energy to take, increasing rate of reaction
explain why rate of reaction decreases in terms of concentration
the rate decareses as concentration of reactants decreases
how to determine the ratio of volumes on a graoh with two lines
draw a horizontal line for the same mass.
read of the volumes produced
put them in a ratio
how does increasing concentration affect rate of reaction
rate of reaction increases
