Kinetics Study on the Reaction between Sodium Thiosulphate and Hydrochloric Acid - MeitY OLabs

Summary

This experiment investigates the kinetics of the reaction between sodium thiosulphate and hydrochloric acid. By varying the concentration of sodium thiosulphate in five conical flasks, the experiment measures the time taken for a cross mark to become invisible due to the formation of insoluble sulphur. The results are used to establish a relationship between reaction rate and sodium thiosulphate concentration, demonstrating that the rate of reaction is directly proportional to its concentration. A graph of 1/t against concentration yields a straight line, confirming this proportionality.

Takeaways

• 🧪 The experiment studies the kinetics of the reaction between sodium thiosulphate and hydrochloric acid.
• ⚗️ A 0.1 molar sodium thiosulphate solution and 1 molar hydrochloric acid are used in the experiment.
• 🔬 Five conical flasks (A, B, C, D, E) are prepared with varying volumes of sodium thiosulphate solution.
• 💧 Distilled water is added to each flask to ensure a total volume of 50 milliliters.
• 📏 The concentrations of sodium thiosulphate in flasks A to E are 0.02, 0.04, 0.06, 0.08, and 0.1 molar, respectively.
• ⏱️ A stopwatch is started as hydrochloric acid is added to each flask, monitoring the time until the cross mark becomes invisible.
• 🌫️ The formation of insoluble sulphur causes the solution to turn milky and opaque.
• 📊 The experiment is repeated for each flask, recording the time taken for the cross mark to disappear.
• 📈 A graph is plotted of 1/t against the concentration of sodium thiosulphate, showing a direct proportionality.
• 🔗 The rate of reaction is directly proportional to the concentration of sodium thiosulphate, as indicated by the linear graph.

Q & A

What is the purpose of the experiment described in the script?

The experiment aims to study the kinetics of the reaction between sodium thiosulphate and hydrochloric acid.

What solutions are used in the experiment?

0.1 molar sodium thiosulphate solution and 1 molar hydrochloric acid are used.

How are the concentrations of sodium thiosulphate prepared in the flasks?

Different volumes of distilled water are added to achieve concentrations of 0.02, 0.04, 0.06, 0.08, and 0.1 molar in flasks A, B, C, D, and E, respectively.

What is the significance of the white tile with a cross mark?

The cross mark serves as a visual indicator to determine when the solution becomes opaque due to the formation of insoluble sulphur.

What is the procedure for starting the reaction in flask A?

After placing flask A over the cross mark, 10 milliliters of 1 molar hydrochloric acid is added, followed by shaking and observing for opacity.

How is the time measured during the experiment?

A stopwatch is started immediately after adding the hydrochloric acid, and it is stopped when the cross mark becomes invisible.

What does the reaction's milky appearance indicate?

The milky appearance indicates the formation of insoluble sulphur, which obscures the cross mark.

What trend is observed when plotting the graph of 1/t against sodium thiosulphate concentration?

A straight sloping line is obtained, indicating that 1/t is directly proportional to the concentration of sodium thiosulphate.

What conclusion can be drawn from the experiment regarding reaction rates?

The rate of reaction between sodium thiosulphate and hydrochloric acid is directly proportional to the concentration of sodium thiosulphate.

How is the experiment repeated for other flasks?

The same procedure is followed for flasks B, C, D, and E by adding 10 milliliters of hydrochloric acid and recording the time taken for the cross mark to disappear.