I've never had any trouble with using the "as-pasted" graphics, but sometimes have had to generate high-resolution schemes separately in Chemdraw or whatever software I was using.

Hi Motoball

Due to having a shortage of info based on the extraction I'm trying to carry out I'm unable to provide you with answers for some of your questions but hope this helps.

The starting material will be: White Ginger (from Southern Asia)
The compound I need to isolate is: DPPH (2,2-diphenyl-1-picrylhydrazyl) due to its ability to boost the immune system.
The sample matrix: Ethyl Acetate in Hexanes
And the scale of this endeavour is low g of matrix

Hope this helps Motoball, please let me know what you thing.


Thanks

Hi guys,
So i got the K1 value for this reaction wich was done using HCL
Now i have to plot the graph of k1 vs H3O.
The pka of hcl is -7
what would be [H3O]


I know that [H3O]+ = [H]+

attempt :
pka= -logka= -7
logka= 7
ka=10^7
ka= x^2/ (3.0M - x) aprrox = x^2/3.0M
1.0 * 10^7 = x^2/3.0M

x= [H3O]

Basically I have to make an ammonium molybdate solution, but I won't be able to filter it for about 72 hours. I'm worried that will be too long based on the nature of the solution. The USP method says "Allow to stand for 48 hours, and filter through a fine porosity, sintered-glass crucible. This solution deteriorates upon standing and is unsuitable for use if, upon the addition of 2 mL of dibasic sodium phosphate TS to 5 mL of the solution, an abundant yellow precipitate does not form at once or after slight warming. If a precipitate forms during storage, use only the clear supernatant" The way I'm reading this, it seems like it deteriorates over a longer period of time, not in a matter of days, and if it does form precipitate within the few days I haven't filtered it, it should be ok.....right???

For overall dilution factor, I know you're supposed to get the individual dilution factor then multiply them so would it be DF = 30 * 50/16?

Thanks!