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Chemistry--- 1 day to go= desperation kicking in (1 Viewer)

wanted4911

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ok This is the last day and god I'm shitting it! don't get me wrong but my parents are looking forward for the school certificate:bomb:

ok Chemistry part of Science. Damn i hate it

its hard to imagine. Combustion, precipitation, neutrilisation, corrosion etc. Also DNA, i get it but some of it is confusing.

I know what they all mean but when it comes to doing it chemically, im a goner.:mad1:

Anyone can help? i did this revise in a month crap in like 2 weeks and finished the science and maths. But thats like going fast as through it so i get the basics for the exam. Hist im ok a bit of bullshitting will do me for a band 4. Geo don't even ask, im not taking the 2 subjects but i hate a band 3 in my paper.

ok i got approximately 20 hours including sleeping time. What do you suggest?:confused:

Anyways im kinda screwed for the SC so yeah lol. English i didn't even study

Trials i got 62/90 for it. I enjoy Science and maths, but Science's got alot of info. So yeah

by the way whos leaving straight after yr 10? As in leaving in week 6 and coming back on next year?

so yeah hopefully everything will be fine.

Plea to the board of studies""""Give us an easy exam"""

cya guys
 

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First off, the chemistry part of the school certificate is extremely easy from what I've seen in the past papers. All they are are just common basic reactions. For example, add magnesium to sulfuric acid and what do you get: hydrogen and magnesium sulfate. Just make sure you know the word equations for each reaction (acid/metal, acid/carbonate, acid/base, neutralisation, combustion, stuff like that) and how to do simple chemical formulas (learn basic valencies). You probably need to know abit about synthesis, displacement and decomposition reactions too.

It's all basic stuff, you don't need to go into detail. You don't need to know how to do the more complicated chemical thingies.
 

jellybelly59

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Chemistry in school certificate is usually just word equations.... u need to remember them cause they'll almost certainly pop up in the SC.

DNA- remember the structure and features of DNA like what a strand of DNA is made from ATCG (adenine, thymine, guanine and cytosine correct me if im wrong:D) hydrogen bonds and yerh stuff like dat... Remember ur punnet squares, if u can learn a bit on transcription and mRNA (just that the T changes to a u during transcription)... genes and chromosomes (2 of each gene i think), remember meiosis and mitosis... if u remember dat stuff u should go fine

gl all :D
 

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Haha, I'm screwed for genetics because we have this sub teacher. She's from Normo and she seems to reiterate that fact 5+ times every lessons, for some reason or another. But yeah, we've learnt shit all. :)
 

jellybelly59

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not sure bout synthesis but i think transcription is where the DNA strand is for a moment split up.... the strand of DNA is copied and is changed into mRNA... thats when the t changes to a U... their sent to the ribosomes and dere split into 3 letters (e.g ATA) and dere like amino acids i think..... 20 of them make a specific polypeptide which turns into a protein....
 

Zephyrio

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DUDE

Just relax kk? A lot of the reactions in the exam are really basic! So just know the basics really really well, and in terms of biology, learn the structure of DNA, historical developments, how to draw its structure. stuff like that. You're also unlikely to be tested on mRNA, tRNA etc.

Like instead of questions like these: Describe the production of proteins (protein synthesis) with mention of DNA.

You'll probably get questions like this: What are the building blocks of proteins? To which you would answer amino acids. Yeah?
 

militiaman

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Does anyone know where some good notes on Chemical equations are? I know they're only word equations, but seriously I haven't gotten a good grasp on it. The teacher I have is the worst at explaining it, and when we've asked him questions in past papers he's gotten them wrong.

This is the biggest thing I'm worried about for science.

Example 2003 SC:

acid + akali > salt + ???

And this is not in multiple choice.
 

jellybelly59

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umm... from the top of my head here are some basic ones

acid + base > salt + water
acid + metal > salt + hydrogen
acid + metal oxide > salt + water
acid + carbonate > salt + water + carbon dioxide

also ppl remember what u need to do to prove if gases are the products of ur reactions like limewater and poptest or relighting a flame on the stick test..... hahaha

btw gl all :D
 

militiaman

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^ We need to remember all those individually? Surely there must be some way which you can work it out. Hmm, I think I might learn what an alkali is first...
 

fayeee

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militiaman said:
^ We need to remember all those individually? Surely there must be some way which you can work it out. Hmm, I think I might learn what an alkali is first...
an alkali is a base
[isn't it?]
 

Kujah

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Alkali is a substance with a pH>7.

You would not need to know anything about protein synthesis- it's too technical for the SC, but not the HSC :)
 

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Yeah, alkali = base. Anyone want to tell me about the DNA models? Stuff like Watson-Crick? :)

Sorry for hijacking the thread abit. :p
 

jellybelly59

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lol ATCG = sugar phosphates i think... someone confirm that for me :D lol umm in between is hydrogen bonds.... A complements T. C with G. T changes to u during transcription... the shape is a double helix... dats it
 

militiaman

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What I mean is are you supposed to know all those individually for acids? Or do you work those out by thinking "OK, a base has to have an X in it and an acid has to have Z in it so the other product must be Y" or are you just remembering that list?
 

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So for the Watson-Crick model, all I gotta do is make the DNA a double-helix-weird-shappy thing, right? Then add and label the sugar, phosphates, nitrogen bases and that's it? :)
 

Kujah

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And know that the copying of DNA is called replication.
 

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militiaman said:
What I mean is are you supposed to know all those individually for acids? Or do you work those out by thinking "OK, a base has to have an X in it and an acid has to have Z in it so the other product must be Y" or are you just remembering that list?
Remember the word equation then apply it. For example:

2HCl + CaC03 = ?
You know that acid/carbonate reaction gives you water + carbon dioxide + salt
Therefore, 2HCl + CaCO3 = C02 + H2O + salt
The salt must equal to Calcium Chloride because they're the only thingies left
Therefore you have the equation, 2HCl + CaCO3 = CO2 + H2O + CaCl2
This is easy because it balances out, for some equations, you might have to change how many reactions and products you get and blah blah blah
 

Kujah

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jellybelly59 said:
hydrogen bonds.... but yerh i think thats around it
Don't need to know about hydrogen bonding.
 

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