PERCOBAAN KALORIMETRI (PRAKTIKUM KALORIMETER SEDERHANA)

Summary

In this practical lab session, students determine the enthalpy change of the reaction between HCl and NaOH using a simple calorimeter. The procedure involves measuring the initial temperatures of HCl and NaOH, mixing them in the calorimeter, and recording the temperature change as the reaction occurs. The final temperature of the solution is observed, and key calculations are made, including the heat change (Q) and moles of the reactants, to determine the enthalpy change (ΔH) of the reaction. Students also apply the formula for heat capacity and specific heat to analyze the reaction energetics.

Takeaways

• 😀 The experiment aims to determine the enthalpy change of the reaction between HCl and NaOH using a simple calorimeter.
• 😀 50 mL of HCl solution and 50 mL of NaOH solution are used in the experiment.
• 😀 The initial temperature of both HCl and NaOH solutions is measured at 25°C using separate thermometers.
• 😀 A simple calorimeter is prepared, with a thermometer attached to a stopper and placed in the calorimeter.
• 😀 The HCl and NaOH solutions are mixed in the calorimeter, and the container is sealed tightly to prevent heat loss.
• 😀 The temperature change is observed until the temperature stabilizes at the highest point, which reaches 32°C.
• 😀 The initial and final temperatures are recorded for both solutions, and the change in temperature is used for further calculations.
• 😀 Students are instructed to calculate the heat of the reaction (Q) using the formula Q = mass × specific heat × temperature change.
• 😀 The specific heat capacity of the solution is assumed to be 4.2 Joules per gram Kelvin, and the mass is considered 1 gram per mL.
• 😀 Moles of HCl and NaOH are calculated using the formula mol = concentration × volume (in liters).
• 😀 The enthalpy change (ΔH) of the reaction is then calculated using the formula ΔH = Q reaction / moles of the reactants.

Q & A

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

The purpose of the practicum is to determine the enthalpy change of the reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) using a simple calorimeter.

What are the initial temperatures measured for HCl and NaOH in the experiment?

The initial temperature of both the HCl and NaOH solutions is 25°C.

How much of HCl and NaOH solutions are used in the experiment?

50 mL of HCl solution and 50 mL of NaOH solution are used in the experiment.

What is the final temperature observed during the reaction?

The final temperature observed during the reaction is 32°C.

How is the calorimeter used in the experiment?

The calorimeter is set up with a thermometer attached to a stopper, and it is closed tightly once the HCl and NaOH are mixed inside. The temperature change is then monitored until it becomes constant.

What is the specific heat capacity of the solution used in the calculation?

The specific heat capacity of the solution is 4.2 Joules per gram Kelvin.

How is the heat absorbed or released by the solution calculated?

The heat absorbed or released by the solution is calculated using the formula Q = m * C * ΔT, where m is the mass of the solution, C is the specific heat capacity, and ΔT is the temperature change.

What formula is used to calculate the moles of HCl and NaOH?

The moles of HCl and NaOH are calculated using the formula: moles = Molarity (M) * Volume (L).

What is the formula used to calculate the enthalpy change (ΔH) of the reaction?

The formula used to calculate the enthalpy change (ΔH) of the reaction is ΔH = Q reaction / moles.

What assumption is made about the density of the solution in the calculation?

It is assumed that the density of the solution is 1 gram per milliliter (1 g/mL).