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##### Organic Chemistry Forum / Re: hydrolysis of sucrose

« Last post by**arpaco**on

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**Today**at 06:03:09 AMJanuary 24, 2021, 06:32:23 AM

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I dont' understand very well when a distortion (for example z axis elogantion/compression) can occour in an octahedral complex

-I've read that can occour when the six ligand are different...for example [M(Cl)_{4}O_{2}] ^{+/- n} ...the oxygen ligands can cause a compression on the z-axis

- In another example I've seen a complex with the same 6 ligands [M(NH3)_{6}] that can follow an octahedral distartion....but usually when is a d^{8}

So can a distortion occour in both cases??

THANKS

-I've read that can occour when the six ligand are different...for example [M(Cl)

- In another example I've seen a complex with the same 6 ligands [M(NH3)

So can a distortion occour in both cases??

THANKS

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It all started with the question (which is in the title of the thread) whether SO2Cl2 can be used to synthesize acid chlorides. Meter showed a reaction that also includes DMF (he claims the reaction is from Wikipedia).

You started a discussion about the advisability of using DMF, and then the discussion went sidetrack.

You started a discussion about the advisability of using DMF, and then the discussion went sidetrack.

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I dont understand how this is relevant for the question from Meter?

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Please read the **forum rules**.

What have you tried so far?

Titration is a simple stoichiometry combined with n=CV.

What have you tried so far?

Titration is a simple stoichiometry combined with n=CV.

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For solids and liquids "w/w" is a default. Solutions of some biochemical (biomedical) reagents may be given in "w/v". Solutions of ethanol only may be given in "v/v" or proofs (but should be stated).

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What is the default unit of concentration of commercial reagents when only "%" is stated and no "w/w", "w/v" or "v/v"?

H2SO4 98% (w/w or w/v?)

H2O2 30% (w/w or w/v?)

Thanks!

H2SO4 98% (w/w or w/v?)

H2O2 30% (w/w or w/v?)

Thanks!

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Hi can someone teach me how to complete a table and solve for the following: molarity of Ca, Moles Ca, Milligrams Ca, Titer Ca (mg Ca/mL EDTA)? I am only given molarity of EDTA, final burette reading (mL).

Thank you!!

Thank you!!

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I think "volatility" is one of those words that expresses a general concept (liability to evaporate) but is not a precisely defined technical term. For example for an ideal mixture of A and B, the partial pressure of A vapour is xI am getting a bit confused about this, well I'm sure that if we have the partial pressure of a component doubled (we can also refer to partial pressure by saying vapour pressure of the component in the mixture, because we're talking about a liquid mixture), then we have the double of the particles of that component as the pressure only depends on the number of particles when the solution is ideal. In conclusion, so far I only found out this about volatility:_{A}P°_{A}, where x_{A}is the mole fraction of A in the liquid and P°_{A}is the vapour pressure of pure A. The total vapour pressure of the mixture is given by

P = x_{A}P°_{A}+ x_{B}P°_{B}

Now I think that saying the volatility of A is twice that of B is ambiguous, because "volatility" is not precisely defined. It could mean

P°_{A}= 2P°_{B}

or it could mean

x_{A}P°_{A}= 2x_{B}P°_{B}

The latter corresponds to your option 2; option 1 is ambiguous - is it referring to vapour pressures of pure A and B, or of A and B in the mixture?

"Volatility itself has no defined numerical value, but it is often described using vapor pressures or boiling points (for liquids)",

while in my notes there's written "if P°A = p°B, then A and B have the same volatility". Considering that the right answer turned out to be the first option, I guess my teacher had the pure component vapour pressure as a definition of volatility.

Anyway, maybe I can't understand what the vapour pressure of the pure component is, I'd say it's the pressure the component would exert if that liquid was alone in the same container, but this way it looks quite the same as the definition of partial pressure.. Where is the mistake? Thanks for your time.

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I think "volatility" is one of those words that expresses a general concept (liability to evaporate) but is not a precisely defined technical term. For example for an ideal mixture of A and B, the partial pressure of A vapour is x_{A}P°_{A}, where x_{A} is the mole fraction of A in the liquid and P°_{A} is the vapour pressure of pure A. The total vapour pressure of the mixture is given by

P = x_{A}P°_{A} + x_{B}P°_{B}

Now I think that saying the volatility of A is twice that of B is ambiguous, because "volatility" is not precisely defined. It could mean

P°_{A} = 2P°_{B}

or it could mean

x_{A}P°_{A} = 2x_{B}P°_{B}

The latter corresponds to your option 2; option 1 is ambiguous - is it referring to vapour pressures of pure A and B, or of A and B in the mixture?

P = x

Now I think that saying the volatility of A is twice that of B is ambiguous, because "volatility" is not precisely defined. It could mean

P°

or it could mean

x

The latter corresponds to your option 2; option 1 is ambiguous - is it referring to vapour pressures of pure A and B, or of A and B in the mixture?