dilution question - (Apr/14/2009 )

What is the formula for this:
If I need to dilute Solution A 1:2000 in 100ml of water, how much of Solution A do I use?

claritylight on Apr 14 2009, 01:06 PM said:

Is this a homework question?

Clare on Apr 14 2009, 07:16 AM said:

No it is not.

I got 20ul in 100ml. Is that right or what is the right formula?

you want to dilute 2000 times, final volume is 100 mL
the formula is 100 mL/2000 = 0.05 mL = 50 µL

just to be sure, if you dilute 2000 times 50 µL you get 100 mL (0.05 * 2000 = 100 mL)

an other way to see it is that a 1000 times dilution would be 100 µL in 100 mL
2000 is twice more diluted than a 1000 times dilution, so you take twice less (i.e. 50 µL)

Hi,
Use N1 X V1=N2 X V2 formula for this kind of questions.
Where, N1 is conc., molarity, per cent or any other unit of stock solution. V1 is the volume of the stock solution. N2 is conc., molarity, per cent or any other unit of final/required solution and V2 is the volume of of final/required solution.
Make sure to fill in any three values and you will get the fourth.
Hope this will help you.