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molarity and what does the M stand for

how do you find grams when solving molarity questions



this is the how many grams of sodium chloride will be required to make a 1.45M  solution of 555mLproblem:


First the M stands for Molarity.  Molarity is defined as the number of moles of solute per liter of solution.  Thus the equation for molarity is

Molarity = moles of solute / liters of solution


In your sample problem you are givent the molarity (1.45M) and the volume (it is necessary to convert 555mL into .555 L).  Plug into the molarity equation and solve for moles of solute (NaCl in this case).

Finally, convert the moles of NaCl into grams using the formula mass of NaCl (58.5 g/mol).