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March 19, 2024, 07:45:15 pm

Author Topic: VCE Chemistry Question Thread  (Read 2308991 times)  Share 

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usernameincorrect

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Re: VCE Chemistry Question Thread
« Reply #6510 on: August 15, 2017, 06:08:27 pm »
0
Hello! Ive attached a picture of the skeletal structure for the alkane c3h5Br2, which i got from Pubchem. Can anyone explain what the tiny arrow head means? I know that the alkane is missing one H. Ive asked teachers in my school but no one knows, so i think it may be a non standard thing? It's been bugging me, hope someone knows!

sweetiepi

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Re: VCE Chemistry Question Thread
« Reply #6511 on: August 15, 2017, 06:16:19 pm »
0
Hello! Ive attached a picture of the skeletal structure for the alkane c3h5Br2, which i got from Pubchem. Can anyone explain what the tiny arrow head means? I know that the alkane is missing one H. Ive asked teachers in my school but no one knows, so i think it may be a non standard thing? It's been bugging me, hope someone knows!
Hey!
Using my chemistry drawing program, that arrow could mean that it is absolute; which refers to the spatial arrangement of the atoms of a chiral group. I believe this may be outside of what you need to know for VCE chem :) (I'll check the study design again later :) )
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Bri MT

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Re: VCE Chemistry Question Thread
« Reply #6512 on: August 15, 2017, 07:39:44 pm »
+2
Anyone had a sac on organic compunds/reactions yet? (chap 10/11) if so what did they test you on. Feel like my teacher isnt giving us much of a guide on what to expect :/

Yeah, mine was split into 2 components. The first was about organic compounds & reaction pathways & was based off a SAC we did, and the second was on analytical techniques and was mainly involved combining information from different graphs to determine what compound was being represented.

Make sure you are familiar with the conditions required for different reactions, and can "fill in the blanks" if given a starting and ending molecule. Also make sure that you know what the different techniques are useful for and can interpret them. Good luck :)

usernameincorrect

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Re: VCE Chemistry Question Thread
« Reply #6513 on: August 17, 2017, 09:20:09 pm »
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Hey!
Using my chemistry drawing program, that arrow could mean that it is absolute; which refers to the spatial arrangement of the atoms of a chiral group. I believe this may be outside of what you need to know for VCE chem :) (I'll check the study design again later :) )

Thanks! What's the name of the software you use?

sweetiepi

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Re: VCE Chemistry Question Thread
« Reply #6514 on: August 17, 2017, 09:30:32 pm »
+1
Thanks! What's the name of the software you use?
Most welcome!
I use ChemDraw, which I use for most of my assignments for my course :) (It's licensed by Monash, so I'm not too sure how much it costs outright :) )
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Lavar Big BBB Balls

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Re: VCE Chemistry Question Thread
« Reply #6515 on: August 19, 2017, 11:04:39 pm »
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Hi,

Could I have some help with b and c http://imgur.com/a/ojbQP

The answer for b just gave it in moles so I can't tell what I'm doing wrong in my working but I was not confident. I'm not sure if I need to include M(Na) in the total molar mass?

Sine

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Re: VCE Chemistry Question Thread
« Reply #6516 on: August 19, 2017, 11:14:10 pm »
+5
Hi,

Could I have some help with b and c http://imgur.com/a/ojbQP

The answer for b just gave it in moles so I can't tell what I'm doing wrong in my working but I was not confident. I'm not sure if I need to include M(Na) in the total molar mass?
remember molar mass is the sum of the atoms molar masses not the product
so where you have (23)(16)(35.5)  you should have (23 + 16 + 35.5) I think this is just a silly mistake ahah
should change your answer and give and also give a different answer for (c)

Hopefully this helps you!

Lavar Big BBB Balls

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Re: VCE Chemistry Question Thread
« Reply #6517 on: August 20, 2017, 01:04:13 am »
0
remember molar mass is the sum of the atoms molar masses not the product
so where you have (23)(16)(35.5)  you should have (23 + 16 + 35.5) I think this is just a silly mistake ahah
should change your answer and give and also give a different answer for (c)

Hopefully this helps you!
Yeah, not sure what happened to my brain there lol. Thanks

LPadlan

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Re: VCE Chemistry Question Thread
« Reply #6518 on: August 20, 2017, 09:52:06 pm »
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Why does 2-chloro-2-methylpropane when mixed with ethanol, hcl and potassium permangenate form a white precipitate of silver chloride?

peterpiper

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Re: VCE Chemistry Question Thread
« Reply #6519 on: August 20, 2017, 10:10:44 pm »
+1
Why does 2-chloro-2-methylpropane when mixed with ethanol, hcl and potassium permangenate form a white precipitate of silver chloride?

Where did the silver come from? That doesn't make much sense because you can't have silver chloride without there being silver ions present...
2017: VCE COMPLETED

LPadlan

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Re: VCE Chemistry Question Thread
« Reply #6520 on: August 20, 2017, 10:24:57 pm »
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Where did the silver come from? That doesn't make much sense because you can't have silver chloride without there being silver ions present...
Apologies, there was silver nitrate present in the solution aswell

peterpiper

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Re: VCE Chemistry Question Thread
« Reply #6521 on: August 21, 2017, 12:00:40 am »
+4
Apologies, there was silver nitrate present in the solution aswell

It's because you mixed the silver nitrate and the HCl solution together. Ag+ makes an insoluble compound with any halides, eg. Cl-, I-, Br- -- it's what you learn for gravimetric which is background knowledge to VCE chem. It's just one of those things you have to remember and rote learn.
« Last Edit: August 21, 2017, 12:06:43 am by peterpiper »
2017: VCE COMPLETED

KANYEWEST

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Re: VCE Chemistry Question Thread
« Reply #6522 on: August 21, 2017, 07:20:00 pm »
0
Any one here done the Practical investigation for finding energy content in Biscuits/peanuts?
Under food chemistry!
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BlinkieBill

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Re: VCE Chemistry Question Thread
« Reply #6523 on: August 25, 2017, 11:55:00 am »
0
Hey, is gravimetric analysis still in the year 12 course?
Thanks
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xghostariax

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Re: VCE Chemistry Question Thread
« Reply #6524 on: August 25, 2017, 07:09:48 pm »
+1
Hey, is gravimetric analysis still in the year 12 course?
Thanks
I'm currently in year 12 and no, it's not in the course. Only volumetric analysis is in the course. :)