PRAKTIKUM (2) FAKTOR-FAKTOR YANG MEMPENGARUHI LAJU REAKSI

Summary

This experiment explores the factors influencing the rate of reaction, particularly the effect of temperature on the reaction between sodium thiosulfate (Na2S2O3) and hydrochloric acid (HCl). The process involves heating Na2S2O3 to different temperatures (26°C, 36°C, and 46°C) and measuring the time it takes for the reaction to turn the solution cloudy, indicating the formation of sulfur. The experiment demonstrates how reaction rate increases with temperature, as observed through varying reaction times. Key variables include temperature (independent), HCl concentration (constant), and reaction time (dependent), showcasing the relationship between temperature and reaction speed.

Takeaways

• 😀 The experiment involves testing the effect of temperature on the reaction rate using sodium thiosulfate (Na2S2O3) and hydrochloric acid (HCl).
• 😀 Various tools are used in the experiment, including a graduated cylinder, beaker, thermometer, spirit lamp, and paper with a cross for visibility.
• 😀 The reaction between Na2S2O3 and HCl causes the solution to become cloudy, and the cross beneath the solution disappears when the reaction is complete.
• 😀 The first trial is conducted at room temperature (around 26°C), and it takes 48 seconds for the cross to disappear.
• 😀 In the second trial, Na2S2O3 is heated to 36°C, and the reaction time decreases to 12 seconds.
• 😀 The third trial involves heating Na2S2O3 to 46°C, further decreasing the reaction time to 13 seconds.
• 😀 The script explains how the reaction time decreases with the increase in temperature, demonstrating the relationship between temperature and reaction rate.
• 😀 A general rule is that for every 10°C increase in temperature, the reaction rate approximately doubles.
• 😀 The observed reaction produces sulfur (S), sulfur dioxide (SO2), and salt (NaCl), with sulfur forming a white precipitate that obscures the cross.
• 😀 The experiment emphasizes that the independent variable is temperature, the controlled variable is the concentration of HCl, and the dependent variable is the reaction time or rate.

Q & A

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

The purpose of the experiment is to study the effect of temperature on the rate of the chemical reaction between sodium thiosulfate (Na₂S₂O₃) and hydrochloric acid (HCl).

What happens when sodium thiosulfate reacts with hydrochloric acid?

When sodium thiosulfate reacts with hydrochloric acid, sulfur (S) is produced, which causes the solution to become opaque and the cross symbol placed under the reaction vessel to disappear.

What are the key variables in this experiment?

The key variables are: the independent variable (temperature), the dependent variable (time for the cross to disappear, which represents the rate of reaction), and controlled variables (volume of sodium thiosulfate, concentration of hydrochloric acid, and the type of equipment used).

How is temperature varied in the experiment?

Temperature is varied in three steps: starting at 26°C, then increasing to 36°C, and finally reaching 46°C. These temperature changes allow the effect of temperature on the reaction rate to be observed.

What is the significance of the cross disappearing during the experiment?

The disappearing cross indicates the point at which the solution becomes opaque due to the formation of sulfur, signaling the completion of the reaction. The time it takes for this to happen is used to measure the reaction rate.

How does the reaction rate change with temperature according to the experiment?

As the temperature increases, the reaction rate accelerates, which is evident from the decreasing time it takes for the cross to disappear at higher temperatures.

What were the times recorded for the reaction at different temperatures?

At 26°C, the reaction took 7 minutes and 48 seconds. At 36°C, the reaction occurred in 12 seconds, and at 46°C, the reaction occurred in 13 seconds.

Why does the reaction rate increase with temperature?

The reaction rate increases with temperature because higher temperatures cause molecules to move faster, leading to more frequent collisions between particles, which increases the likelihood of the reaction occurring.

What equation represents the relationship between temperature and reaction rate in this experiment?

The equation V2 = 2^(ΔT/10) × V1 is used to show that for every 10°C increase in temperature, the reaction rate doubles.

What are the products of the reaction between sodium thiosulfate and hydrochloric acid?

The products of the reaction are sodium chloride (NaCl), sulfur (S), sulfur dioxide (SO₂), and water (H₂O).