help! on one dot point (1 Viewer)

[eunkuk91]

can anyone give me a hand on how to get a 6 mark on the dot point/question
"discuss the need for alternative sources of the compounds presently obtained from the petrochemical industry" ?

 

[crammy90]

can anyone give me a hand on how to get a 6 mark on the dot point/question
"discuss the need for alternative sources of the compounds presently obtained from the petrochemical industry" ?

Discuss: identify issues and provide reasons for or against.
Presently compounds obtained for the petrochemical industry come from the cracking of those long chained (c10-c40 i think) in crude oil (petroleum) and natural gas - either steam thermal or catalytic cracking on the fractions recieved from distillation. This is a concern as crude oil supplies are expected to diminish in the next 10yrs and natural gas in the next 100; due to them both being non-renewable resources (take millions of years to produce). This will see prices rise proportionally to their limiting amounts and so economic stress will be placed on families internationally. There will be a decline in transport, the amount of people owning cars and could result in a depression. Wars may break out in the search for the last oil supplies.
The products from this cracking process are the petrochemicals (i.e. deisel, LPG etc) which we use to maufacture plastics and as fuel. When used, they emmit greenhouse gases to contribute to global warming (90% USA greenhouse contributed from fossil fuel consumption) and release oxides of nitrogen and sulphur contributing to acid rain (throw in those equations). They also release heavy metals which are toxic. As populations and the rise in motor vehicles increases, along with increases in taxations on fossil fuels in attempts to minimise their use and encourage the development of alternatives, we must search elsewhere for these founding chemicals if we are to, in the future, have a source of energy for fuel, plastic manufacturing and other industrial processes.

i didnt have my notes. ill look at them and correct the figures as i wouldnt bet my life on them. im sure other people have stuff to add

 

[eunkuk91]

tyvm but i dont think that will get me 6 marks no offence

 

[namburger]

Just spam EVERYTHING you know even if it is mildly related for a 6 marker lol
Off the top of my head:


There is a need because: petrochemicals are non-renewable and they are pollutants

• Fossil fuels have accumulated over millions of years
• Analysts predict that we are going to use up all available oil reserves in the next few decades making them scarce and expensieve
• Petrochemicals used as fuels are pollutants because the products of combustion, carbon dioxide and water contribute to thermal pollution and global warming
• Polymers obtained from the petrochemical industry are non-biodegradable which contributes to increase in number and size of landfills
• An alternative resource would be biomass.
• Biomass is any material produced from living organisms (plant material)
• An example would be cellulose which has the basic carbon structure of petrochemicals
• The disadvantage of biomass are that land must be cleared in order to grow crops. The problems that arise include soil erosion,salinity etc
• Advantage: Renewable resource if used as a fuel because when combusted, its products (carbon dioxide and water) are returned back into the photosynthesis cycle
• There is a need for alternative resources for the production of materials in the future

 

[crammy90]

edited my post
should get 6 i rekon
i dno if id talk about cellulose or alternatives and their advantages unless their wasnt another question on them in the paper

 

[namburger]

Isn't the question refering to alternate resources anyway?
I would of talked about much more stuff in an exam like ethanol's use as a car fuel in Brazil which shows how alternative fuels are already being used to replace petrochemicals.

I think HSC markers only mark on what is correct and related to the question so i would of spammed the crap out of this question haha

BTW,

release oxides of nitrogen and sulphur contributing to acid rain

The release of these oxides occur in the combustion chamber of cars regardless if it were a petrochemical or biomass. It comes from the air, not the type of fuel.

 

[crammy90]

Combustion of fossil fuels generates sulfuric, carbonic, and nitric acids, which fall to Earth as acid rain, impacting both natural areas and the built environment. Monuments and sculptures made from marble and limestone are particularly vulnerable, as the acids dissolve calcium carbonate.

from wikipedia under fossil fuels. I dont think it would hurt to throw it in.
We could broaden to talk not just about cars but also furnaces and what not but eh i dno.
i think with this question youve just got to think about what is in the syllabus and then apply it lol.

Petrochemicals are chemicals made from compounds in petroleum or natural gas. Currently Australia has petroleum reserves that will last about ten years and natural gas reserves that will last about one hundred years. Fossil fuels have taken hundreds of millions of years to accumulate. Over 95% of fossil fuel is burnt as a source of energy and once burnt, fossil fuels are no longer available. Less than 5% of fossil fuel is used to make plastics and only a small percentage of that plastic is recycled. If energy and material needs are to be met in the future, alternative sources will be needed as fossil fuel sources are used up.

HSC online dont mention it and her question was taken as a syllabus dot point and there are other dot points concerning ethanol and biomass so id say to really maybe only subtly mention them in the end like "biomass....and ethanol has had sucess in Brazil" etc.
just my thoughts

 

[namburger]

i think with this question youve just got to think about what is in the syllabus and then apply it lol.

talk about everything as long as its correct. AND even if its not in the syllabus, examiners like show-offs