LAB Report 3 CHM256 PDF - lab PDF

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BASIC ANALYTICAL CHEMISTRY(CHM 256)EXPERIMENT 5ACID-BASED TITRATION IIDETERMINED THE PERCENT(W/W) OF THE ACTIVE INGREDIENTIN ASPIRIN TABLETNAME: 1. MUHAMMAD HAZIQ IMRAN BINAZMIR2. MUHAMMAD NAQIB SYAKIRTHAHILSTUDENT ID: 1. 20192275842. 2019240332COURSE: CHM 256GROUP: AS1204LDATE OF EXPERIMENT: 13/04/...

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BASIC ANALYTICAL CHEMISTRY (CHM 256) EXPERIMENT 5 ACID-BASED TITRATION II DETERMINED THE PERCENT(W/W) OF THE ACTIVE INGREDIENT IN ASPIRIN TABLET NAME:

1. MUHAMMAD HAZIQ IMRAN BIN AZMIR 2. MUHAMMAD NAQIB SYAKIR THAHIL

STUDENT ID:

1. 2019227584 2. 2019240332

COURSE:

CHM 256

GROUP:

AS1204L

DATE OF EXPERIMENT:

13/04/2021

DATE OF SUBMISSION: LECTURER’S NAME:

ZURHANA BINTI MAT HUSSIN

OBJECTIVE: To determine the percent (w/w) of the active ingredient, acetlysalicyclic acid (C9H8O4) in aspirin tablet.

APPARATUS AND REAGENTS APPARATUS

REAGENTS

Volumetric flask:250ml (1) 100 ml (2) Retort stand 250 ml conical flask flask (x3)

1M NaOH-50 ml or 100 mL (shared) Indicator: Phenol red or phenolphthalein Aspirin tablet (Brand: Disprin or Visprin, 300 mg ASA) 0.1M HCL (250ml)

20 ml,25 ml pipette Burette Weighing boat/bottle/paper Filter tunnel Dropper

PROCEDURE: Part A: Preparation of solution 1M NaOH solution (50ml),0.1M HCL solution (250ml) and 0.05M Na2CO3 (100ml) was prepared as it was learned from previous experiments.

Part B: Hydrolysis of aspirin 1. One commercial aspirin tablet (300 mg ASA) was collected from your lecturer. The brand names, the manufacturer’s name and % content (mass) of the active ingredient in the tablet (use 2 tablets if the ASA content is 100 mg) was collected.

2.

The aspirin tablet was weighed accurately in a weighing paper and the tablets was transferred into a 250 ml conical flask.

3. 25 ml of 1.0M NaOH solution (use pipette) and 25 ml of water was added to the tablet. This mixture was heated until it boils for about 10 minutes in order to hydrolyze the aspirin.

4. The solution at room temperature was cooled then it was transferred quantitatively into 250ml volumetric flask. The solution to the mark carefully was diluted using dropper when the level is close to the calibration mark.

Part C: Standardization of HCL solution: The procedure as in Experiment 3B was followed to standardize your HCL solution. The data in Table 5.2 was recorded.

Equation: Na2CO3 + 2HCL = 2naCL + H2O + CO2

Part D: Back Titration: 1. 20 ml of aspirin solution was pipette into a 250 ml conical flask.

2. 1-2 drops of phenol red or phenolphthalein indicator was added.

3. The aspirin solution in the 250ml conical flask was titrated with the diluted 0.1M HCL solution from the burette while the flask was shake until the indicator changes colour (phenol red: light red to light yellow; phenolphthalein: pink to colourless). The readings at the end point of the titration were recorded.

4. It was repeated 2-3 times and the recordings was recorded in a table.

5. The %w/w of acetylsalicyclic per tablet was calculated.

RESULTS/DATA: Table 5.1

Commercial/brand name of aspirin Name of tablet manufacturer Mass per tablet of active ingredient (acetylsalicyclic acid) stated on the label Mass of aspirin tablet Calculated %w/w

Millisprin KCK Pharmaceutical 900 mg 1.1567 g 77.81 %

Table 5.2: Standardization of HCL solution.

Titration Final burette reading (ml) Initial burette reading (ml) Volume of HCL used (ml)

Rough -

1 23.70

2 23.70

3 23.80

-

0.00

0.00

0.00

-

23.70

23.70

23.80

A) Average volume of HCL: 23.73 ml B) Volume of Na2CO3 used: 25.00 ml C) Molarity of Na2CO3 used:0.05M

Table 5.3: Titration of aspirin solution with HCL

Titration Final burette reading (ml) Initial burette reading (ml) Volume of HCl used (ml)

Rough -

1 13.90

2 13.10

3 13.10

-

0.00

0.00

0.00

-

13.90

13.10

13.10

A) Average volume of HCl: 13.37 ml B) Initial volume of NaOH used to hydrolyze aspirin: 25.00 ml

QUESTIONS 1. a) Based on the data obtained in Table 5.2 calculate the exact molarity of HCl 2. b) Using back titration method, calculate the % (w/w) aspirin in the aspirin tablet. i) Calculate the initial mole of NaOH used for hydrolysis. ii) Based on Equation (2), calculate the mole of excess (unreacted) NaOH. iii) Calculate the mole of NaOH that has actually reacted with acetylsalicylic acid. iv) Based on Equation (1), calculate the mole of acetylsalicylic acid in the solution. v) Calculate the mass then the % w/w of acetylsalicylic acid in the tablet.

ANSWER

CONCLUSION In conclusion, my partner and I learn the procedure and calculation on how to determine the percent (w/w) of the active ingredient, acetlysalicyclic acid (C9H8O4) in aspirin tablet which was 61.37% per tablet....