Experiment No. 8 PREPARATION AND STANDARDIZATION OF NaOH SOLUTION Materials: NaOH pellets (AR grade) Potassium acid phthalate, KHP (AR grade) Phenolphthalein indicator Distilled/Deionized water Procedures A. Preparation of NaOH Solution 1. Weigh roughly 10.00 g of NaOH pellets (AR grade) in a previously tared small beaker 2. Add previously boiled and cooled distilled water to dissolve the NaOH 3. Pour the NaOH solution into a 1 L volumetric flask 4. Rinse the beaker with distilled water and pour the rinsing into 1 L volumetric flask 5. Add enough distilled water to complete the volume to 1 L 6. Store the solution in a 1 L stock bottle with plastic cap 7. Label properly B. Standardization of NaOH solution using a primary standard: 1. Weigh accurately 1.5 - 2.0 g of KHP (previously dried @ 110 C in an oven for 1 hour) into an Erlenmeyer flask. 2. Dissolve with 50 mL of distilled water by shaking the flask 3. Add 2 drops of phenolphthalein indicator 4. Titrate to a faint pink color using a base buret 5. Perform 2 determinations. 6. Determine the normality of NaOH solution. Formulas/Equations: A. Preparation of Solution M = g NaOH MM NaOH x L solution B. Standardization using a primary standard MM of KHP = 204.22 g/mole moles NaOH = moles KHP MxV NaOH = g KHP MM KHP M NaOH = g KHP MM KHP x V NaOH Name : Frencess Kaye Simon Group No: Individual Year & Section: BSMLS-1A Date Performed: 03-19-2022 Experiment No. 8 PREPARATION AND STANDARDIZATION OF NaOH SOLUTION I. Objectives: (Formulate your own) 1. With a sodium hydroxide solution of around 10.00 g pellets (AR grade), measure the concentration and determine the solution concentrations. 2. Determine the normality of NaOH solution. II. Materials (Based on the procedure above) A. Laboratory Apparatus 1. Erlenmeyer Flask 2. Graduated Cylinder 3. Pipette 4. 5. 6. Burette Weighing Bottle Polyethylene Bottles B. Chemicals/ Reagents 1. NaOH Pellets 2. Phenolphthalein 3. Standard HCL Solution III. Data & Results Trial 1 Trial 2 1.6850 1.6895 Final Reading-NaOH, mL 33.15 33.40 Initial Reading-NaOH 0.00 0.00 Volume NaOH used 0.03315 0.0334 Molarity of NaOH, moles/L 0.2489 0.2477 Wt. of KHP, g Average Molarity, M 0.2483 Note: Concentrations should be expressed up to the 4th decimal place, for example 0.1008 M CALCULATIONS: Refer to the formulas and equations above Preparation of Solution: Note: Use the information in your procedure to get the molar concentration of your NaOH solution M = g NaOH MM NaOH x L solution = 10.00g NaOH (40.00g/mol) (1L) = 0.25 mol/L Standardization of NaOH solution Trial 1 M NaOH = g KHP MM KHP x V NaOH = 1.6850g (204.22g/mol)(0.03315L) = 0.2489 mol/L Trial 2 M NaOH = 1.6895g (204.22g/mol)(0.0334L) = 0.2477 mol/L Average = 0.2489 + 0.2477 2 = 0.2483 M IV. ANALYSIS/INTERPRETATION OF RESULTS • The table's data can be used to calculate the concentration of solution of sodium hydroxide The amount of NaOH used in the second step has increased trial. However, as the trials progressed, the molarity of NaOH (moles/L) declined. Both trials have an average molarity of 0.2483 M. V. CONCLUSION • Standardization is the process of precisely determining a solution's concentration (molarity). Titration is an analytical process that is frequently used in standardization. In the course of titration, an exact volume of HCl is reacted with a known amount of NaOH. The 'end point' of the titration is identified using an indicator, phenolphthalein, as the color of the solution changes to light pink. This experiment aims to use titration under established art to standardize a sodium hydroxide solution. VI. REFERENCES • UIC Lab Manual • https://www.youtube.com/watch?v=GPn4Urq6ZHw • https://www.youtube.com/watch?v=VV3CQe10MpI&t=508s Experiment No. 9 PREPARATION AND STANDARDIZATION OF HCl SOLUTION Materials Hydrochloric Acid Standard NaOH solutiom phenolphthalein Preparation of HCl solution: 1. Pour around 50 mL of distilled water into a 1-L volumetric flask 2. Add 21.0 mL of HCl (12 M) cautiously and gradually shaking after addition 3. Mix well, pour HCl solution into a stock bottle (glass is preferred) 4. Label and preserve for future use. {note: solution should be restandardized prior to use.} Standardization of HCl solution using a secondary standard: 1. From a Geissler buret (or delivery pipet), run down 20 mL of the prepared HCl solution into a 250-mL Erlenmeyer flask 2. Add enough distilled water to make the volume to around 50 mL 3. Add 2 drops of phenolphthalein indicator 4. Titrate with prepared NaOH in Expt. 8 using a Mohr buret to a light pink color end point 5. Perform 2 determinations 6. Determine the molarity of HCl solution Equation: HCl + NaOH → NaCl + H2O moles HCl = moles NaOH mL HCl x M = mL NaOH x M M of HCl = mL NaOH x M mL HCl Name :_____________________ Group No. :______________ Year & Section : _________ Date Performed :_________ Experiment No. 9 PREPARATION AND STANDARDIZATION OF HCl SOLUTION I. Objective/s: • to make a precise concentration standard solution that can be used to standardize other solutions • The exact molarity of a hydrochloric acid solution must be determined. II. Materials (Based on the procedure above) A. Laboratory Apparatus 1. Volumetric Flask 2. Stock Bottle (Glass) 3. Geissler buret 4. Erlenmeyer Flask 5. Mohr buret B. Chemicals/ Reagents 1. Hydrochloric Acid 2. Standard NaOH solution 3. Phenolphthalein III. Data & Results Trial 1 Trial 2 Volume HCl used, mL 20.00 20.00 Final Reading-NaOH, mL 19.50 39.10 Initial Reading-NaOH 0.00 19.50 0.0195 L 0.0391 L Volume NaOH used Average Molarity of NaOH (from 0.2483M Expt.8) Molarity of HCl 0.2438 Average Molarity of HCl 0.4888 0.3663M Note: Concentrations should be expressed up to the 4th decimal place, for example 0.1008 M Calculations : Trial 1 M of HCl = mL NaOH x M mL HCl = (19.50 mL) (0.25 mol/L) 20.00mL = 0.2438 mol/L Trial 2 M of HCl = (39.10 ml) (0.25 mol/L) 20.00 Ml = 0.4888 mol/L Average = 0.2438 + 0.4888 2 = 0.3663M IV. Analysis • The information in the table can be used to calculate the hydrogen chloride solution concentration. The amount of HCl utilized has increased in the second trial. Furthermore, as the trials went, the HCl Molarity rose. In both trials, the average molarity of hydrogen chloride was 0.3663 M. V. CONCLUSION • It aims to be exactly the same as experiment laboratory 8, it standardized, same goes to it distilled water was added first and HCl to be able to accurately determined the solution concentration. VI. REFERENCES • UIC Lab Manual • https://www.youtube.com/watch?v=lXzAB8woAd8 Experiment No. 10 PREPARATION & STANDARDIZATION OF EDTA SOLUTION Materials: Disodium ethylenediaminetetraacetate Calcium carbonate as primary standard Dilute HCl solution Sodium Hydroxide T.S. Hydroxynapthol blue powder Procedures: A. Preparation of EDTA Solution 1. Dissolve about 4.80 g of EDTA powder in sufficient distilled water in a small tared beaker 2. Transfer the solution to a 250-mL volumetric flask 3. Rinse the beaker with distilled water, adding the rinsing into the flask 4. Dilute to volume with distilled water 5. Standardize the solution using the following procedure B. Standardization of EDTA Solution 1. Weigh accurately 100- 150 mg of primary standard CaCO3 and transfer it to a flask 2. Add 20 mL of distilled water and sufficient diluted HCl to dissolve the carbonate 3. Dilute with distilled water to 100 mL 4. Add 15 mL of NaOH solution (pH should be around 13), then add a pinch of hydroxynapthol blue indicator 5. Titrate the solution with EDTA until it turns into a deep blue color 6. Run a second trial and calculate its molarity Formula: Preparation of EDTA solution M = Disodium EDTA 336.21 g/mole x L solution Standardization of EDTA solution mmol EDTA = mmol CaCO3 mL EDTA x M = wt. of CaCO3 MM of CaCO3 Molarity of EDTA = wt. of CaCO3 100.08 g/mole x L EDTA Name :_____________________ Group No. :______________ Year & Section : _________ Date Performed :_________ Experiment No. 10 PREPARATION & STANDARDIZATION OF EDTA SOLUTION I. Objective/s: • Finding out how to Standardize the ETDA solution • find the molarity of the substance VI. Materials: Beaker Disodium ethylenediaminetetraacetate volumetric flask Calcium carbonate as primary standard burette Dilute HCl solution Pipette Sodium Hydroxide T.S Hydroxynaphthol blue VI. Data & Results: Trial 1 Trial 2 Weight of CaCO3, g 0.1245 0.1312 Final Reading-EDTA ,Ml 25.05 26.20 Initial Reading- EDTA 0.00 0.00 Volume EDTA used,Ml 25.05 26.20 0.0497 0.0500 Molarity of EDTA Average Molarity 0.0499M CALCULATIONS: Preparation: M= = Disodium EDTA 336.21 g/mole x L solution 4.80g EDTA (336.21 g/mol) (0.25L) = 0.0571 mol/L Standardization Trial 1 Molarity of EDTA = = wt. of CaCO3 100.08 g/mole x L EDTA 0.1245g (100.08 g/mole) (0.02505L) = 0.0497 mol/L Trial 2 Molarity of EDTA = 0.0312g (100.08g/moll) (0.0262L) = 0.0500 mol/L Average = 0.0497 + 0.0500 2 = 0.0499M IV. ANALYSIS/INTERPRETATION OF RESULTS • The information in the table can be used to calculate the EDTA solution concentration. In the second study, the amount of EDTA used (mL) was increased. Furthermore, as the trials progressed, the molarity of EDTA increased. In both experiments, the average molarity of EDTA was 0.0499 M. V. CONCLUSION • The principal standard for this experiment was calcium carbonate (CaCo03), while the indicator was Hydroxynaphthol blue powder. EDTA is a water-soluble aminopolycarboxylic acid that belongs to the aminopolycarboxylic acid family. Complexometric titration is used to achieve this chemical standardization. VI. REFERENCES • UIC Lab Manual • https://www.youtube.com/watch?v=jGb6j4uyjOE • https://classroom.google.com/c/NDUzMTkyMTU3ODM2/m/MjI4NDI4MDUxNzMw/de tails