Can someone please write the procedure on how to get the 2 unknown concentration
ID: 693243 • Letter: C
Question
Can someone please write the procedure on how to get the 2 unknown concentrations (please include an example for how to do the calculations) You will be assigned a 200-ml solution of unknown NaOH concentration. You need to determine the concentration. The concentrations will range from approximately 0.080M to 0.125M. You will then use that base to determine the concentration of an unknown HCl solution, of which you will be given 100- mL; concentrations will range from approximately 0.10 to 0.15M No refills will be given. These ranges are approximate. You are expected to follow good lab practices, data recording, and proper calculations to give answers that are accurate and displaying the correct significant figures. Equipment available: 50.00-mL buret, 10 and 20 ml pipets, analytical balances (weight room), glassware in your drawer. Chemicals available: Solid, dried KHP; phenolphthalein indicator, unknown solutionsExplanation / Answer
Molar mass of KHP, MW = 204.23 g/mol
1 mole of KHP reacts with 1 mol of NaOH
1. Weigh 0.6 g of KHP dried solid and dissolve in 20 mL distilled water in a flask.
Moles of KHP = 0.6 / MW
= 0.6 / 204.23 mol
= 2.448 mMol
2. Titrate it against 50 mL of standard NaOH solution filled in the given buret.
Note the volume of NaOH required to neutralize using phenolphthalein indicator (say V1)
V1 (mL) * Molarity of NaOH = Moles of KHP dissolved = 2.448 mMol
3. Calculate Molarity of NaOH.
4. Take 20 mL of unknown HCl solution in a flask.
5. Titrate it against 50 mL of standard NaOH solution filled in the given buret.
Note the volume of NaOH required to neutralize using phenolphthalein indicator (say V2).
Molarity of HCl * 20 mL = Molarity of NaOH * V2 (mL)
6. Calculte molarity of HCl solution.