Ethanol fuel Q (1 Viewer)

[ay_caramba]

How did u guys relate the data in the table to the advantages and disadvantages of using ethanol??

i guess the obvious one would be ethanol is renewable.. since it said in the table that it is made by fermentation while the others said fossil fuels..

what abt the boiling pts they included? has that got anything to do with the volatility of ethanol vs hydrocarbons?

 

[sub]

yeah...ethanol is a kiquid at room temps making it a better fuel than most hydrocarbons listed except octane...heat of combustion as well...more than half taht of octane, even though its less than half the molecular mass, makes it a better fuel...
and finally, ethanol burns cleaner as it requires less O2 to burn "completely"
renewable as well...but u had that...u can talk abt the brazil thingy for disadvantages. eg major land clearing, soil degradation etc.
i think that covers everything i rote...hope that helps

 

[ay_caramba]

yeah...ethanol is a kiquid at room temps making it a better fuel than most hydrocarbons listed except octane...heat of combustion as well...more than half taht of octane, even though its less than half the molecular mass, makes it a better fuel...
and finally, ethanol burns cleaner as it requires less O2 to burn "completely"
renewable as well...but u had that...u can talk abt the brazil thingy for disadvantages. eg major land clearing, soil degradation etc.
i think that covers everything i rote...hope that helps

oh ok i see... thanx
haha brazily thingy yeah i shouldve mentioned that

 

[sub]

i din explicitly mention it, but i sed everything abt it...shoulda sed it tho. damn.

 

[lucyinthehole]

uh.. i think i said that because it has a higher boiling point, it requires a higher energy input (as a disadvatage)... would this be in any way correct?

also, do you think we had to refer to all the 3 columns in the graph, or just any reference would count as a "tick"?

 

[sub]

uh.. i think i said that because it has a higher boiling point, it requires a higher energy input (as a disadvatage)... would this be in any way correct?

also, do you think we had to refer to all the 3 columns in the graph, or just any reference would count as a "tick"?

that last part is for the criteria to decide...sry, cant help there

high energy input...ur burning it? how much more energy do u need? my reasoning was if its a gas, as u use more, the more diluted the fuel becomes, so a liquid/solid fuel is better...thas y its a benefit, cos more constant fuel output in energy...if u kno what i mean. but if u explained it in the exam it could work...

 

[bloodysunday]

umm i dont think that bp has much to do with it since it's about combustion more than anything else.

also, do you think we had to refer to all the 3 columns in the graph, or just any reference would count as a "tick"?

i hope that any reference would be ok cause i only referred to octane and ethanol... fingers crossed

 

[The Bograt]

- can be transported as a liquid (boiling point)
- renewable, as opposed to the other petrol chemicals made from crude oil and gas
- doesn't combust to form alot of energy
- engines must be modified
- combusts cleaner since it has oxygen in it, making it better for the environment
- requires lots of biomass --> land
I think something else too maybe, can't remember

 

[sub]

u missed large enrgy inputs for fermentation and distillation...but yeah thats it basically.

 

[The Bograt]

Mine should be enough for full marks shouldn't it? How many marks was it?

 

[bloodysunday]

5 marks, and im hoping mine'll be good enough for full since i wrote more than the lines gave me... or is that quantity not quality

 

[sub]

usually they say quality, but if u write more...and dont rite crap u get the marks i make a habit of trying to go over the number of lines given...but sometimes u just cant

 

[Kazuya]

dammit i didn't mention any of the usual stuff cos i thought in your answer you were only supposed to write info you got from the table. Stupid wording again..

 

[sub]

yeah this exam was full of em...esp industrial and the plant site thingy...u could talk about soooo mcuh, but the q made u think u only had to do a little.

they like ppl hu can crap on and on and on...

 

[bloodysunday]

i think that the ethanol question was always gonna be there, they just wanted to screw it round a bit so that they could please their own sadistic little minds *shakes fist* lol

 

[jumb]

I got to a second booklet for this question. Go me!

 

[sub]

damn straight jumb...u show that q hu's boss...howd u find the test tho overall??

 

[xeriphic]

err for me

advantages
oxgenated fuel - complete combustion - reduce pollutants
renewable - fermentation
varies ways to be produced - hydration, fermentation
petrol-ethanol blend reduce toxic emissions by 30% in the atmosphere

disadvantages
engines need modification
low heat of combustion - leads to more energy
inefficient if energy required to tend crops for fermentation comes from fossil fuels
land needed for growing crops - fermentation

 

[Sarzzabelle]

I loved this question coz we did a super-duper big assignment on it.

 

[mushroom_head]

overall for this question i said that it was not a suitable alternative. it was an evaluate or assess question right????? although i did mention some advantages at the beginning of my response