An old bottle of 12.3 M hydrochloric acid has only 33 mL left in it. What is the HCl concentration if enough water is added so that the final volume is 513 mL?
calculate the number of millimoles in the original
12.3 x 33 mmoles
the final volume is 513 ml so the concentration (moles per litre) is
12.3 x 33 mmoles/513 ml