h bond confusion

[inaccensa]

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the q is attached

 

[vnicolas]

I would guess C, I believe that rings like benzene and phenyl are insoluble but this is just my guess.

 

[mikexima]

Here is how I would attack it.

Two factors determine solubility in water, H bonding and polarity, and they take priority in that order.

based on the fact that B&D do not H bond. I would eliminate those.

Then you're left with A & C. both are sterically hindered, although its argueable which is more hindered. Out of the two C is only able to hydrogen bond through offering its Hydrogen while A hydrogen bonds through its nitrogen AND hydrogen. A is also significantly more polar due to lone pair of electrons and would be my guess. Is that the right answer or is there some sort of trick ?

 

[Morsetlis]

A: two possible H-bonds, polar

Phenols are obviously less soluble. N+ hydrocarbons are still hydrocarbons and the N+ is hidden. A is the only one with two possible H bonds.

 

[geeyouknit]

Doesn't the fact that "C" is ionic make it the most attractive to water's polar structure? Wouldn't that make it the most soluble, ie, how readily solute is pulled apart by solvent bonds?

My guess is C.

 

[mikexima]

Doesn't the fact that "C" is ionic make it the most attractive to water's polar structure? Wouldn't that make it the most soluble, ie, how readily solute is pulled apart by solvent bonds?

My guess is C.

C is not ionic. the + referes to the charge on Nitorgen. All bonds are covalent. Ionic bonds are betwen two species with great electronegetivity differences and usually opposite charges. anything from group 1 matched with halogens is inoic, such as NaCl. hence why its Na+ Cl-.

correct answer is A from what i understand

 

[geeyouknit]

C is not ionic. the + referes to the charge on Nitorgen. All bonds are covalent. Ionic bonds are betwen two species with great electronegetivity differences and usually opposite charges. anything from group 1 matched with halogens is inoic, such as NaCl. hence why its Na+ Cl-.

correct answer is A from what i understand

Ionic wasn't the right word, but it's a cation, right? It's like ammonium. There's an overall plus charge on the molecule.

 

[inaccensa]

the answer is C, now I understand the reasoning

 

[kehlsh]

the answer is C, now I understand the reasoning

what is it? does it have something to do with electron donating property of alkyl branch vs electron withdrawing property of benzyl rings???😕

 

[mikexima]

what is it? does it have something to do with electron donating property of alkyl branch vs electron withdrawing property of benzyl rings???😕

trick question. things like this are a waste of time and never appear on mcat. 👎

 

[geeyouknit]

trick question. things like this are a waste of time and never appear on mcat. 👎

Can someone explain why it's C? I'm just wondering if my reasoning is right or if there's a better explanation.

Thanks