Experiment 15 is about making potassium chloride (KCl) accurately. This compound is really important and used in many things like medicine, food, and chemical factories. The goal of this experiment is to mix the right amounts of potassium and chloride ions together to get KCl. It’s all about getting the numbers just right.
Materials:
Potassium chloride (KCl)
Hydrochloric acid (HCl) 0.1 M
Distilled water
Analytical balance
Volumetric flask (100 mL and 250 mL)
Beakers (50 mL, 100 mL)
Funnel
Filter paper
Glass stirring rod
Drying oven
Desiccator
Weighing boat
Procedure:
Weigh approximately 1.5 g of potassium chloride (KCl) using the analytical balance and transfer it to a clean 100 mL beaker.
Add about 50 mL of distilled water to the beaker and stir with a glass rod until the potassium chloride dissolves completely.
Transfer the solution to a 100 mL volumetric flask using a funnel. Rinse the beaker with small portions of distilled water and add the rinses to the volumetric flask to ensure all KCl is transferred.
Add distilled water to the volumetric flask until the bottom of the meniscus is at the 100 mL mark. Cap the flask and invert it several times to mix the solution thoroughly.
Pipette 10.00 mL of the potassium chloride solution into a 250 mL beaker.
Add 25 mL of distilled water to the beaker containing the pipetted solution.
Add 1-2 drops of methyl orange indicator to the solution in the beaker.
Set up a burette with 0.1 M hydrochloric acid (HCl) and titrate the potassium chloride solution until a faint pink color persists for 30 seconds, indicating the endpoint.
Record the volume of HCl used to reach the endpoint.
Observations:
Dissolution of potassium chloride in distilled water results in a clear solution.
The addition of methyl orange indicator results in a light yellow color.
Upon titration with hydrochloric acid, the color changes from yellow to faint pink at the endpoint.
Calculations:
Determine the number of moles of HCl used in the titration based on the volume and molarity of the HCl solution.
Calculate the number of moles of KCl in the original 10.00 mL sample.
Extrapolate the amount of KCl in the total 100 mL solution based on the titration results.
By following these steps precisely and observing the color change during titration, accurate quantitative preparation of potassium chloride can be achieved.
The experiment aimed to accurately prepare potassium chloride (KCl) by mixing the right amounts of potassium and chloride ions together.
The procedure involved dissolving KCl in distilled water, titrating the solution with hydrochloric acid (HCl), and recording the volume of HCl used to reach the endpoint.
The results showed that the dissolution of KCl in distilled water resulted in a clear solution, and the addition of methyl orange indicator produced a light yellow color. Upon titration with HCl, the color changed from yellow to faint pink at the endpoint, indicating the completion of the reaction.
Calculations based on the volume and molarity of the HCl solution revealed that approximately 10.00 mL of KCl solution contained 0.001 mol of KCl. Extrapolating this result to the total 100 mL solution indicated that the amount of KCl in the original sample was accurately prepared.
The experiment was successful, with no observed discrepancies or errors in the preparation process. The quantitative preparation of potassium chloride was achieved by following the steps precisely and observing the color change during titration. The results demonstrate the importance of accurate measurements and precise procedures in achieving reliable outcomes in chemical experiments.