• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

criticise my syllabus summary! (1 Viewer)

brightsea

Member
Joined
Nov 10, 2004
Messages
43
Gender
Female
HSC
2005
Ben, I only did a quick skim but it looks like you've got some good info.

One of the dot points I change though would be

 Explain what is meant by a condensation polymer

Condensation polymers are polymers created by the process of condensation polymerisation.
Since the dot point says "Explain" (Def: Relate cause and effect; make the relationships between things evident; provide why and/or how) it calls for a little more detail. Maybe something a bit more like this: A condensation polymer is a substance/molecule which has been formed when monomer units join together by a reaction which eliminates a small molecule (often water).

Also, (and this is just a personal preference when studying) I'd make your notes into dot point summaries.

Identify the industrial source of ethylene from the cracking of some of the fractions from the refining of petroleum

Fractional distillation = process where hydrocarbons separated through diff b. pts

2 fractions (naptha + LPG [liquefied petroleum gas]) used to manufacture C2H4 ethylene (ethene)

General term to produce ethylene = cracking.

Cracking = long chain hydrocarbon breakdown (C15-100) into shorter/useful hydrocarbons.

Cracking = 2 types

Thermal cracking
High temperatures (450-750 oC) + pressures (up to 70 atm) w/o catalyst
Products obtained = mainly unsaturated hydrocarbons – because C-C bonds break = free radical formation --> various products
(Therefore symbol) thermal cracking favoured over catalytic

Catalytic cracking
Low temperatures (approx 500oC) + low pressures
Zeolite (sodium aluminosilicate) catalyst used = lowers reaction activation energy (therefore) lower temps/pressures.
(Therefore) catalytic cracking = more energy friendly process than thermal

It's just a suggestion, from experience. If you don't want to do it for these notes perhaps do it when the HSC is closer, for revision.
 
P

pLuvia

Guest
Condensation polymerisation involves a reaction between two different monomer units (sometimes called copolymers) where each monomer has two identical functional groups. The formation of a polymer chain occurs when the two functional groups of the monomer units join and a small molecule; in this case water is ejected. Repetition of this mechanism ensures long and linear polymer chains. Examples are given below.
This reaction is the dehydration reaction which removes water molecules from a compound.
You add this bit here
 

iyamahobbit

Resident hobbit
Joined
Oct 23, 2002
Messages
222
Gender
Female
HSC
2004
 Identify the industrial source of ethylene from the cracking of some of the fractions from the refining of petroleum

Fractional distillation is a process by which hydrocarbons are separated through different boiling points into fractions. Two fractions in particular, known as the naptha and LPG (liquefied petroleum gas), are used to manufacture C2H4 ethylene (ethene).

The general term for the process used to produce ethylene is cracking. Cracking is the breakdown of longer chain (C15-100) hydrocarbons into shorter and more useful hydrocarbons. There are two types of cracking, thermal (steam) and catalytic cracking.

Thermal cracking involves high temperatures (450oC to 750 oC) and pressures (up to 70 atmospheres) without the presence of a catalyst. Products obtained from this process are mainly unsaturated hydrocarbons – this is because the carbon-carbon bonds break resulting in the formation of free radicals leading to various products. For this reason, thermal cracking is favoured over catalytic cracking.

Catalytic cracking, on the other hand, uses low temperatures (approximately 500oC) and low pressures with a zeolite (sodium aluminosilicate) catalyst which lower the activation energy required for reactions to take place hence the lower temperatures and pressures. Because of this, catalytic cracking is a more energy friendly process than thermal cracking.
Just a note for general note-making strategy - don't go over the top making notes from books - some of the books were written to the old chem syllabus that had 25% more info, so just cos it's in the textbook doesn't mean you need to know it.

For this dot point, remember that it only says -
 Identify the industrial source of ethylene from the cracking of some of the fractions from the refining of petroleum
As a rule for how much u need to know, when it says "identify", more often than not, all you need to know is actually in the dot point itself.

I can't remember if the syllabus talks about it elsewhere, but for that dot point you definately don't need to distinguish between thermal and chemical cracking. Might be worth a read, but don't waste ur time learning it.
 

Monstar

Member
Joined
Jan 6, 2006
Messages
877
Gender
Male
HSC
2006
Hye guys, the notes in my book are a bit blank about this dot point:

"Describe the addition of water to ethylene results in the production of the ethanol and identity the need for a catalyst in the process and the catalyst used."
 
P

pLuvia

Guest
The additional reaction is hydration which is the addition of water molecules to a compound.
The catalyst used is usually dilute aqueous sulfuric acid and heat is usually needed as well.

CH2=CH2 + H2O ------> CH3-CH2-O-H

-------> dilute sulfuric acid

Here water molecules are added to the ethene which produces ethanol.

NOTE: Dehydration and hydration can be applied to any alkane and alene respectively

Hope this helped :D
 

Monstar

Member
Joined
Jan 6, 2006
Messages
877
Gender
Male
HSC
2006
Well it didnt really say anything about the NEED for a catalyst.

mmm Well i know what a catalyst is for, so should i just put that down?
 

Dreamerish*~

Love Addict - Nakashima
Joined
Jan 16, 2005
Messages
3,705
Gender
Female
HSC
2005
Monstar said:
Well it didnt really say anything about the NEED for a catalyst.

mmm Well i know what a catalyst is for, so should i just put that down?
Yes, it does say "identify the need", but since everyone has such high expectations of short-answer questions, markers will be forced to be picky.

If it was something really difficult to remember, then I'd say forget it, but since it's just a couple of words on the side, it's probably best to put it in. So you would identify the need of the catalyst, and also name it.
 

xvelidras

Member
Joined
Oct 28, 2005
Messages
34
Gender
Female
HSC
2005
Monstar said:
Well it didnt really say anything about the NEED for a catalyst.

mmm Well i know what a catalyst is for, so should i just put that down?
Technically speaking, the catalyst in hydration of ethene is the H+ in the acid. Hence industrially, the use of dilute phosphoric acid, and in the laboratory, dilute sulfuric acid. H+ is required because ethene and water will not readily attack each other, and hence will NOT react to form ethanol. H+ however, acts as an electrophile (electron loving species) and will attack the double bond of ethene. Reactions to complete the hydration of ethene then occur. They will not minus that initial step with the catalyst

Of course, you dont have to learn/write that mouthful. You can utilise what you know about catalysts and APPLY it to this reaction.
-ethene and water will not readily react with each other
-hence, H+ provides the alternative pathway for the reaction to proceed
 

Riviet

.
Joined
Oct 11, 2005
Messages
5,593
Gender
Undisclosed
HSC
N/A
-identify the need for a catalyst...
All you need to say for this part of the dot point is "A dilute sulfuric acid catalyst is used to lower the activation energy for the reaction to proceed." Nice and concise. Even answers the next bit of the dot point too. :)
 

.ben

Member
Joined
Aug 13, 2005
Messages
492
Location
Sydney
Gender
Male
HSC
2006
Does anyone know what to write for the production of transuranic elements and teh difference between that and the production of commerical isotopes?

btw thanks for all the input guys i will post another edited one in a few days.
 

Dreamerish*~

Love Addict - Nakashima
Joined
Jan 16, 2005
Messages
3,705
Gender
Female
HSC
2005
.ben said:
Does anyone know what to write for the production of transuranic elements and teh difference between that and the production of commerical isotopes?

btw thanks for all the input guys i will post another edited one in a few days.
By definition, transuranic elements are those with an atomic number higher than that of uranium (92).

Commercial radioisotopes are those that serve a purpose other than sit there and emit radiation.

Both transuranic and commercial radioisotopes can be made by:
  • Bombarding with neutrons in a nuclear reactor
  • Bombarding with high speed positive particles in a linear accelerator or a cyclotron
The difference between the two would be that when making commercial radioisotopes, there is a known target. For exmaple, we know that to make cobalt-60, cobalt-59 needs to be bombarded with a neutron. So what we'll do is just that.

Transuranic radioisotopes, on the other hand, is something like whacking a neutron or positron into a nuclei and seeing what you get from it. Also note that not all transuranic radioisotopes have commercial use, and that not all commercial radioisotopes are transuranic.
 

beabenn

tambourine man
Joined
Dec 18, 2004
Messages
28
Location
Sydney
Gender
Male
HSC
2005
.ben said:
Does anyone know what to write for the production of transuranic elements and teh difference between that and the production of commerical isotopes?

btw thanks for all the input guys i will post another edited one in a few days.
Basically, what Dreamerish posted is spot on but she's missing one thing:
a chemical equation
so you would use this equation in your answer as a supporting examplke and to illustrate that you have a firm knowledge of the topic.
So cobalt-59 + neutron = cobalt-60
Very simple of course use element notation where Co represents cobalt and "n" represents a neutron also use subscript and superscript to show atomic numbers and atomic weights.
This is very noitty-gritty but often an equation is worth AT LEAST ONE MARK
 

Dreamerish*~

Love Addict - Nakashima
Joined
Jan 16, 2005
Messages
3,705
Gender
Female
HSC
2005
beabenn said:
Basically, what Dreamerish posted is spot on but she's missing one thing:
a chemical equation
so you would use this equation in your answer as a supporting examplke and to illustrate that you have a firm knowledge of the topic.
So cobalt-59 + neutron = cobalt-60
Very simple of course use element notation where Co represents cobalt and "n" represents a neutron also use subscript and superscript to show atomic numbers and atomic weights.
This is very noitty-gritty but often an equation is worth AT LEAST ONE MARK
Absolutely.


I forgot to add that in all short-answer questions, write equations and draw diagrams or flowcharts to clarify your answer.

Pluvia - I think Ben would be using Chemistry Contexts and Chemistry Pathways. I assume our school's not dumping our new Contexts after just one year. They've got something against Conquering, but we know everyone secretly uses it at home.
 
Last edited:

.ben

Member
Joined
Aug 13, 2005
Messages
492
Location
Sydney
Gender
Male
HSC
2006
yes, i will add the equations into the examples thansk for reminding me.

yeh at school we use chemistry contexts and they gave us chemistry pathways. we're probably not gonna dump context cos it looks so new! but that aside ms eastment's got a stack of good bio/chem/phys/maths books for us to borrow!

Just one more question tho, do we need to know about half life and its calculations?

thanks you guys you've been of great help!:)
 

Dreamerish*~

Love Addict - Nakashima
Joined
Jan 16, 2005
Messages
3,705
Gender
Female
HSC
2005
.ben said:
yes, i will add the equations into the examples thansk for reminding me.

yeh at school we use chemistry contexts and they gave us chemistry pathways. we're probably not gonna dump context cos it looks so new! but that aside ms eastment's got a stack of good bio/chem/phys/maths books for us to borrow!

Just one more question tho, do we need to know about half life and its calculations?

thanks you guys you've been of great help!:)
You need to know what half life is and what it means. I don't recall any calculations concerning half-life, so probably not. :p
 
P

pLuvia

Guest
Well you should already know about it, but it's not in the syllabus
 

.ben

Member
Joined
Aug 13, 2005
Messages
492
Location
Sydney
Gender
Male
HSC
2006
ok fantastic. certainly saves a lot of work!

thanks!
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top