User:David E. Volk/Sandbox: Difference between revisions

Revision as of 13:57, 20 June 2009

My Sandbox:

@@ Line 1: / Line 1: @@
 My Sandbox:
 <br>
-'''Molarity''' (M) is a term used in [[chemistry]] to indicate the concentration of a [[solute]] in a [[solvent]], in units of M = [[mole (chemistry)|moles]]/[[liter]].  For a pure compound with virtually no solvent, molarities are in the range of about 10-18 M.  Chemical solutions typically used in labs are often between 10 millimolar (mM) and 1 molar concentrations.  Solutions of biological samples, containing proteins, enzymes or DNA, are more oftenly used in the nanomolar (10<sup>-9</sup> M) or micromolar (10<sup>-6</sup> M) range, up to about 10 mM.  For a solution containing many molecules, each molecule will have a molarity which is independent of the other components, unless they chemically react over time.  Molarity is calculated by dividing the amount (mass) of the chemical being added into a solution by both its molecular mass (molecular weight MW) and the final volume of the solution.
-:<math> M =  \frac{moles}{liter} = \frac{m}{MW*V}</math>
-where
-:''m'' = mass of chemical added, in grams
-:''MW'' = molecular weight (mass), in grams/mole
-:''V'' = final volume of the solution