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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: kenhung123 on May 20, 2010, 05:42:44 pm

Title: Hydrophobic and Hydrophilic
Post by: kenhung123 on May 20, 2010, 05:42:44 pm
How do I know if part of the molecular is hydrophobic or hydrophilic?
I first thought hydrophobic means it can dissolve in non polar substances so it doesn't have any charge, but apparent CH3+ is considered hydrophobic
Title: Re: Hydrophobic and Hydrophilic
Post by: kyzoo on May 20, 2010, 10:01:11 pm
CH3+ is an ion, hence it can form ion-dipole bonds with water molecules
Title: Re: Hydrophobic and Hydrophilic
Post by: Mao on May 21, 2010, 06:21:15 pm
CH3+ is highly unstable, you won't class it as hydrophobic nor hydrophilic. Heck, if you can isolate CH3+, you'll probably get the next Nobel prize for chem.
Title: Re: Hydrophobic and Hydrophilic
Post by: m@tty on May 21, 2010, 07:26:34 pm
If you are referring to the neap test, it is a methyl group. It is hydrophobic because it is non-polar. Though there is probably some more precise reason soon to be given by Mao.
Title: Re: Hydrophobic and Hydrophilic
Post by: Mao on May 23, 2010, 04:24:44 am
What is the original question from the paper?
Title: Re: Hydrophobic and Hydrophilic
Post by: kenhung123 on May 23, 2010, 06:52:40 am
CH3+ is an ion, hence it can form ion-dipole bonds with water molecules
Yea but isn't water polar?

What is the original question from the paper?
I can't find the question now. lol. Well I remember it was a diagram of molecule with various side chains and they asked to circle the part that is considered hydrophobic. Would this by any chance be one of those old questions more related to unit 4?
Title: Re: Hydrophobic and Hydrophilic
Post by: Mao on May 23, 2010, 09:15:43 pm
A methyl group would be considered hydrophobic. A methylium ion is a whole different matter.