Unit 3 Questions MEGATHREAD :)

[DisaFear]

Heinemann Textbook:

However, carbon can form covalent bond with other atoms or groups of atoms. These are called functional groups. A functional group is an atom or group of atoms that give a characteristic set of chemical properties to a molecule containing that group

I'd say yes because it influences the properties of the molecule but i'm not sure. I'd like to find out though. According to this it is so -> http://chemed.chem.purdue.edu/genchem/topicreview/bp/2organic/function.html

Are you sure that link wasn't referring to the Br thingy?

Edit: nvm, read on

[luken93]

Okay, so I've done 3 different exams with 3 different states.

WHAT ARE THE CORRECT STATES FOR THE FERMENTATION OF GLUCOSE -> ETHANOL + CO2!

[scocliffe09]

Is an alkene (C=C bond) considered a functional group?

I think it is, but I'd await confirmation from the higher powers.

Benzene also is...

higher powers?

And TSFX said they aren't "strictly" functional groups... but this was a VCAA sample exam so maybe it is

Benzene is definitely a functional group.
Double bonds are not strictly but can be counted as a functional group according to VCAA, especially if there's nothing else to talk about.

[acinod]

Okay, so I've done 3 different exams with 3 different states.

WHAT ARE THE CORRECT STATES FOR THE FERMENTATION OF GLUCOSE -> ETHANOL + CO2!

Based on past VCAA Assessment Reports:
For fermentation, Glucose and Ethanol are aqueous while CO2 is a gas.
For combustion, O2 and CO2 are gas while Ethanol and H2O could be liquid or gas.

[luken93]

Okay, so I've done 3 different exams with 3 different states.

WHAT ARE THE CORRECT STATES FOR THE FERMENTATION OF GLUCOSE -> ETHANOL + CO2!

Based on past VCAA Assessment Reports:
For fermentation, Glucose and Ethanol are aqueous while CO2 is a gas.
For combustion, O2 and CO2 are gas while Ethanol and H2O could be liquid or gas.

Cheers!

[Dr.Lecter]

edit

[mickeymouse]

simple question but I can't remember.... converting g/L to mol/L we divide the value by the molar mass?

[luken93]

yep. if you ever forget, think about 18g/L of water, then you have 1mol/L

[nacho]

what about ppm
i forgot those.
for solids and liquids! help

[Greatness]

ppm = micrograms per gram = milligrams per litre = micrograms per millilitre

[homosapiens]

1. What kinds of reactions does benzene undergo? I would have thought combustion and addition (because of the double bonds) but apparently it's substitution, not addition? Is this because the shape must be maintained?

2. When say ethane reacts with chlorine when there's UV light, is CH3CH2Cl the only possibility, ie can CH2ClCH2Cl also be formed? And if so is it just that chloropropane is more likely than 1,2-dichloropropane...

[nacho]

WHAT DO I  NEED TO KNOW FOR ASPIRIN??
holy crap, im gonna cram for aspirin 6 hours after accounting exam tmrw..

[thushan]

1. What kinds of reactions does benzene undergo? I would have thought combustion and addition (because of the double bonds) but apparently it's substitution, not addition? Is this because the shape must be maintained?

2. When say ethane reacts with chlorine when there's UV light, is CH3CH2Cl the only possibility, ie can CH2ClCH2Cl also be formed? And if so is it just that chloropropane is more likely than 1,2-dichloropropane...

1. [OUT OF COURSE] Benzene undergoes substitution because the fact that it's aromatic makes it highly stable; if you try to add to benzene you have to break this stability, this aromaticity, and that's unfavourable. Benzene instead undergoes substitution, that's correct. You don't need to know this though - I think all you need to know is that benzene does not act like a normal alkene.

2. Yes, you can get two chlorines thrown in. In fact, you can get as many chlorines thrown in as you want; it depends on the relative proportions of chlorine and ethane - whether chlorine is in excess or not.

[nacho]

okay
i still dont get the diffrence between
beta-d-glucose and galactose
they look the exact same?

[thushan]

Beta-d-glucose and Galactose differ at carbon 4; in galactose the OH sticks up, in glucose the OH sticks down.