### GENERAL CHEMISTRY 1140 SOLUTION CONCENTRATION - MOLARITY PREPARATION DILUTION   MEASURING REAGENTS MOST SOLIDS CAN BE WEIGHED ACCURATELY BUT..... HCl IS A GAS! NaOH CAN'T PURCHASE 100% PURE MANY REACTIONS HAVE TO BE RUN BY ADDING ONE SOLUTION TO ANOTHER AgNO3(s) + NaCl(s) ---> No Reaction AgNO3(aq) + NaCl(aq) ---> AgCl(s) + NaNO3(aq) MEASURE VOLUME OF A SOLUTION USING GRADUATED CYLINDERS, MOHR PIPETS, VOLUMETRIC PIPETS, VOLUMETRIC FLASKS. IF WE USE A SOLUTION WE NEED TO KNOW HOW MUCH OF THE REACTANT IS IN THE SOLUTION? WE NEED A CONCENTRATION OF THE SOLUTION!   MOLARITY = M A ONE MOLAR SOLUTION HAS ONE MOLE OF SOLUTE DISSOLVED IN ONE LITER OF SOLUTION   1 M = 1 mol/1 liter = 1 mol/L  3.07 M = 3.07 mol/L    ASSUME I HAVE ONE LITER OF A ONE MOLAR SOLUTION OF NaCl ASSUME I POUR 500 mL OF THE SOLUTION INTO A 500mL CONTAINER WHAT IS THE CONCENTRATION OF THE SOLUTION IN THE 500 mL CONTAINER?   IF I HAVE 100 mL OF A 1 M HCl SOLUTION, HOW MANY MOLES OF HCl DO I HAVE?   IF I HAVE 75 mL OF A 2.0 M NaOH SOLUTION, HOW MANY MOLES OF NaOH DO I HAVE?   WHAT IS THE MOLARITY OF A 500.0 mL SOLUTION PREPARED FROM 18.2 g NaOH?   MOLARITY = MOLES/LITER FIND MOLES AND FIND LITERS!!!     YOU NEED 100.0 mL OF A 0.478 M SODIUM HYDROXIDE SOLUTION. HOW MUCH SOLID SODIUM HYDROXIDE MUST YOU WEIGH OUT?     PROBLEMS: YOU CANNOT OBTAIN PURE SODIUM HYDROXIDE SOLID SODIUM HYDROXIDE PICKS UP MOISTURE FROM THE AIR PREPARE A CONCENTRATED SOLUTION AND DILUTE IT!   HOW MUCH 6.00 M NaOH IS REQUIRED TO PREPARE 100.0 mL OF 0.478 M SODIUM HYDROXIDE SOLUTION?    NOTE: A 0.200 M SOLUTION OF SODIUM SULFATE WOULD BE: 0.400 M IN SODIUM ION 0.200 M IN SULFATE ION

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