Unit 3 Questions MEGATHREAD :)

[Andiio]

Rf = Retardation and not retention factor...right? Haha insecurity.

I thought temperature would change the movement of both the component & the solvent itself in equal proportions like what you said, so Rf remains the same? :\

[nacho]

its the same thing,
but there is also
retention time, Rt, which is different

[thushan]

Rf = Retardation and not retention factor...right? Haha insecurity.

I thought temperature would change the movement of both the component & the solvent itself in equal proportions like what you said, so Rf remains the same? :\

Yeah, that's what I thought. I'm now trying to see why QAT says otherwise...

[Water]

Rf = Retardation and not retention factor...right? Haha insecurity.

I thought temperature would change the movement of both the component & the solvent itself in equal proportions like what you said, so Rf remains the same? :\

Yeah, that's what I thought. I'm now trying to see why QAT says otherwise...

How can this possibly be true? They all have different MP/TP for the components. Their movements would be distinctly different to one another.


Its like comparing beef to pig, both have different rates that they will cook. Amping up the temperature won't mean, they will cook at the same speed.

My take on it *

[nacho]

question:
Whats the relationship between amino acids, proteins and enzymes
are proteins polymers of amino acids?

are pH indicators composed of amino acids? ie do the constituents consist of amino acids? (i've just heard of ph indicators as 'buffer solutions' so many times, so was just curious)
chemically,  what is a 'buffer'?

[mickeymouse]

buffer maintains pH of a solution, zwitterions are buffer solutions

[Sakigami]

I have a quick question,
As you know the hydroxide ion OH- is formed in an acid/base reaction with water acting as an acid. If NaOH is a strong base then, do the OH groups in amino acid side groups do the same thing in certain pH solutions or are they completely unrelated things? :S

[DisaFear]

Proteins are biochemical compounds consisting of one or more polypeptides
And a polypeptide is a bunch of amino acids, which are the monomers

Right?

[thushan]

I have a quick question,
As you know the hydroxide ion OH- is formed in an acid/base reaction with water acting as an acid. If NaOH is a strong base then, do the OH groups in amino acid side groups do the same thing in certain pH solutions or are they completely unrelated things? :S

Careful here. NaOH only acts as a base here because it has Na+ and OH- already in the lattice; OH- acts as the base.

With the hydroxy groups, eg. Ser-CH2-OH, they are definitely not basic. If anything they are very very very very very weakly acidic (weaker acids than even water).

[Greatness]

question:
Whats the relationship between amino acids, proteins and enzymes
are proteins polymers of amino acids?

Amino acids form polypeptides which form proteins and enzymes.

[pi]

Proteins are biochemical compounds consisting of one or more polypeptides
And a polypeptide is a bunch of amino acids, which are the monomers

Right?

I'd just say proteins are long polypeptides, insulin is the smallest with 51 amino acids (i think). Both have amino acids as monomers

[Sakigami]

I have a quick question,
As you know the hydroxide ion OH- is formed in an acid/base reaction with water acting as an acid. If NaOH is a strong base then, do the OH groups in amino acid side groups do the same thing in certain pH solutions or are they completely unrelated things? :S

Careful here. NaOH only acts as a base here because it has Na+ and OH- already in the lattice; OH- acts as the base.

With the hydroxy groups, eg. Ser-CH2-OH, they are definitely not basic. If anything they are very very very very very weakly acidic (weaker acids than even water).

Alrighty, thanks for that.

[mickeymouse]

how do the H NMR peaks split for butane?

[jane1234]

how do the H NMR peaks split for butane?

One triplet and one quartet I'm fairly sure, someone correct me if I'm wrong...

Also, what's the difference between distilled water and deionised water and what is each used for?

[mickeymouse]

okay kinda confused... how come the two CH2 in butane has a quartet peak but the CH2 in propane has a peak split into 7?