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Question: Dilution - (Sep/24/2008 )

Dear all,

Consider this

M1V1=M2V2

Say I have V2 as 100mL and V1 determined to be 2mL (let's exclude M shall we?), I'd do this: In a volumetric flask, I'll add the 2mL of my stock and top up with, say, distilled water until it reaches the 100mL mark. Now, someone told me it's the same as adding 2mL to 98mL of distilled water. No big difference in the resulting solution I presume?

And then came the argument about 1X and 50X. Which is more diluted? 1X or 50X. I came across TAE buffer with a 50X label and the one used in the tank is 1X. Do we use the M1V1 in dealing with solutions having #X?

Thanks and have a great day.

-jchchye-

QUOTE (jchchye @ Sep 24 2008, 06:10 PM)
Dear all,

Consider this

M1V1=M2V2

Say I have V2 as 100mL and V1 determined to be 2mL (let's exclude M shall we?), I'd do this: In a volumetric flask, I'll add the 2mL of my stock and top up with, say, distilled water until it reaches the 100mL mark. Now, someone told me it's the same as adding 2mL to 98mL of distilled water. No big difference in the resulting solution I presume?


yes, no difference

QUOTE (jchchye @ Sep 24 2008, 06:10 PM)
And then came the argument about 1X and 50X. Which is more diluted? 1X or 50X. I came across TAE buffer with a 50X label and the one used in the tank is 1X. Do we use the M1V1 in dealing with solutions having #X?

Thanks and have a great day.


1x is more diluted than 50x.

50x means 50 times more concentrated than 1x.

If you want to make 1L of 1x using 50x stock, then diluted 20ml of 50x with 980ml of distill water (or put 20ml of 50x into a measuring cylinder and add distill water to 1000ml mark)

M1=1, V1=1000ml, M2=50, V2=?
1 x 1000ml=50 x V2
V2=20ml

Hope this may help.

-Minnie Mouse-

The reason for making 50x stock is to save time weighting the chemical... it is much easier to dilute solution than weight the chemical.

-Minnie Mouse-

Thanks minnie!

-Dreamchaser-