Calculate concentration in molarity (mole/ liter) for a solution containing 50 mg hydrochloric acid (HCl) in 500 ml.

General information:
Molar concentration is calculated using the following equation:

Concentration = (number of moles)/ (volume in liter)
Number of moles = (mass in grams)/ (molar mass)

Molar mass (molecular weight) for HCl = 36.46 g/ mole

Calculations:
Mass of HCl in grams = 50 mg × (0.001 g/ mg) = 0.05 g
Volume of solution in liters = 500 ml × (0.001 liter/ ml) = 0.5 liter
Number of moles in solution = (0.05 g)/ (36.46 g/ mole) = 0.0014 mole
Concentration = (0.0014 mole)/ (0.5 liter) = 0.0028 mole/ liter

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