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Preparation of a %NACL solution - (Aug/12/2013 )

Sorry for this basic question on a professional forum!!

 

it has been a while since I worked in the preparation of stock solutions and now am back to learning happily.

 

I just need to prepare a 1056 ml solution (not water) containing 2.1% NACL. Shall I just add 21 g of NACL and make it up to 1056 and If so I need to first dilute the salt to make it up, would not this change the final concentration?

 

Appreciate your input!!

 

-Dima-

22.176g NaCl in 1056ml solutions?

-Adrian K-

So I just add it up? i thought there is an equation to convert ml into g since 2.1% may be expressed as w/w rather than w/v . could be i am complicating the simple issue. Thx for the reply!

-Dima-

In practice, % usually is meaning  "w/v" or "g/ml"

Can refer to this promega's technical manual on the way they suggest to prepare 10% SDS Solution, 100g in final volume of 1000ml solutions:

http://www.promega.com/~/media/Files/Resources/Technical%20References/Recipes%20For%20Common%20Lab%20Solutions.pdf

-Adrian K-

% usually means grams/100 ml.  It's an ugly standard, but there it is. Perhaps justified by noting that 100 ml weighs 100 g, so you can think of this a bit like a w/w measurement, but this is wrong in more complex situations.

-phage434-

Many many thanks for the continuous supportive forum!!

-Dima-