Praktikum Sifat Koligatif Larutan Penurunan Tekanan Uap

Agus Kamaludin

31 Dec 202008:02

Summary

TLDRIn this educational video, Melanie, a chemistry education student from UIN Sunan Kalijaga, Yogyakarta, conducts a simple experiment to demonstrate the effect of solutes on vapor pressure. She uses three glasses of water, adding salt and sugar to two of them, and observes the amount of condensation on the lids after a day. The results show that pure water has the highest vapor pressure, followed by the sugar solution, and the salt solution has the least. Melanie explains that the presence of solutes reduces vapor pressure due to increased intermolecular forces, making it harder for water to evaporate. An animation is provided to illustrate the process, concluding with the principle that more solutes lead to lower vapor pressure.

Takeaways

🧪 The experiment conducted is a simple laboratory practice about the lowering of vapor pressure.
👩‍🔬 Melanie, a student from the Faculty of Chemical Education at UIN Sunan Kalijaga, Yogyakarta, presents the experiment.
🔬 The experiment aims to understand the impact of dissolved substances on vapor pressure in solutions.
🏡 The experiment is designed to be replicable at home using common household items.
📝 Materials used include three glasses, lids, a spoon, water, sugar, salt, and a baby bottle for measuring water.
💧 The procedure involves filling the glasses with water and adding sugar and salt to two of them, respectively.
⏱️ The glasses are then covered and left to sit for approximately a day to observe the results.
🌡️ The results show that the glass with pure water has the most condensation, indicating the highest vapor pressure.
🔬 The presence of dissolved substances in a solvent lowers the vapor pressure due to increased intermolecular forces.
📉 As the concentration of the solute increases, the vapor pressure of the solution decreases.
🎥 An animation is provided to illustrate the process of vaporization and the effect of solutes on vapor pressure.

Q & A

What is the main topic of the video script?
-The main topic of the video script is a simple experiment on the reduction of vapor pressure.
Who is the speaker in the video script?
-The speaker is Melanie, a student from the Faculty of Chemical Education at UIN Sunan Kalijaga, Yogyakarta.
What is the purpose of the experiment described in the script?
-The purpose of the experiment is to determine the effect of adding a solute on the vapor pressure of a solution.
What materials are used in the experiment?
-The materials used in the experiment include three glasses, three glass covers, a spoon, water, sugar, salt, and a baby bottle to measure the water.
How much water is added to each glass in the experiment?
-100 milliliters of water is added to each glass.
What solutes are added to the glasses and in what quantity?
-One spoonful of salt is added to the second glass, and one spoonful of sugar is added to the third glass.
What is observed after the experiment is conducted for a day?
-It is observed that the glass with pure water has the most vapor, the glass with saltwater has less, and the glass with sugar water has a moderate amount of vapor.
What does the observation indicate about the vapor pressure of the solutions?
-The observation indicates that the vapor pressure of pure water is higher than that of the sugar and salt solutions, with the sugar solution having a higher vapor pressure than the salt solution.
Why does water adhere to the glass cover?
-Water adheres to the glass cover due to the process of evaporation and the presence of vapor pressure within the closed container.
What causes the difference in the amount of water droplets on the covers of the glasses with different solutions?
-The difference is caused by the varying intermolecular forces between the solute and solvent molecules, with pure water having weaker intermolecular forces leading to faster evaporation and more water droplets.
What conclusion can be drawn from the experiment regarding the effect of solutes on vapor pressure?
-The conclusion drawn from the experiment is that the presence of solutes in a solvent causes a reduction in vapor pressure, known as Raoult's Law.
What additional aid is provided to help understand the process of evaporation?
-An animation is provided to illustrate the process of evaporation, showing the difference between pure water and a solution with a solute.

Outlines

00:00

🔬 Introduction to the Experiment on Vapor Pressure Reduction

Melanie, a student from the Faculty of Chemical Education at UIN Sunan Kalijaga, Yogyakarta, introduces a simple experiment on the reduction of vapor pressure. She explains that vapor pressure reduction occurs when the pressure of a solvent's vapor decreases due to the presence of a solute. This experiment can be conducted at home using common household items. The purpose of the experiment is to determine the effect of adding a solute on the vapor pressure of a solution. The materials needed include three glasses, lids, a spoon, water, sugar, salt, and a measuring cup. The experiment involves filling the glasses with water, adding salt to one and sugar to another, and then observing the results after a day to see which glass produces the most vapor.

05:00

🌡️ Understanding Vapor Pressure through Experimentation

The second paragraph delves into the results of the experiment, which show that the glass with pure water produces the most vapor, indicating a higher vapor pressure compared to the solutions with salt and sugar. The explanation provided is that the intermolecular forces between the solute and solvent molecules affect the vapor pressure. The presence of solute molecules increases the intermolecular forces, making it harder for the solvent to evaporate, thus reducing the vapor pressure. An animation is mentioned to help visualize the process of evaporation and how the addition of a solute impacts the vapor pressure. The conclusion is that the more solute added to a solvent, the lower the vapor pressure will be, as the solute molecules hinder the evaporation of the solvent.

Mindmap

Keywords

💡Vapor Pressure

Vapor pressure is the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases in a closed system. In the context of the video, vapor pressure is central to understanding how the addition of solutes to a solvent affects the rate of evaporation. The video demonstrates that the vapor pressure of pure water is higher than that of solutions containing solutes like salt or sugar, leading to different rates of evaporation.

💡Solvent

A solvent is a substance that dissolves a solute to form a solution. Water is the primary solvent in the video, used to create solutions with different solutes. The video explores how the presence of solutes in a solvent affects its vapor pressure, which is a fundamental concept in chemistry and physics.

💡Solute

A solute is a substance that is dissolved in a solvent to form a solution. In the video, salt and sugar are used as solutes added to water. The addition of these solutes changes the vapor pressure of the water, illustrating the impact of solutes on the physical properties of a solvent.

💡Solution

A solution is a homogeneous mixture of two or more substances. The video discusses solutions of water with different solutes (salt and sugar) and how these solutions have different vapor pressures compared to pure water. Understanding solutions is crucial for grasping the experimental outcomes presented.

💡Evaporation

Evaporation is the process by which molecules in a liquid state transition into a gaseous state. The video script describes an experiment where the rate of evaporation from different solutions is observed, linking it to the concept of vapor pressure and the presence of solutes.

💡Concentration

Concentration refers to the amount of solute present in a given amount of solvent or solution. The video implies that the concentration of solutes in a solution affects its vapor pressure, with higher concentrations generally leading to lower vapor pressures.

💡Chemical Potential

Chemical potential is a measure of the tendency of particles to disperse in a system at a given temperature and pressure. In the video, the concept is related to how solutes in a solvent affect the tendency of the solvent to evaporate, with different solutes altering the chemical potential and thus the vapor pressure.

💡Colligative Properties

Colligative properties are properties of a solution that depend on the ratio of the number of solute particles to the number of solvent particles, not on the nature of the particles themselves. Vapor pressure lowering is a colligative property, and the video demonstrates this by showing how the addition of solutes to water reduces its vapor pressure.

💡Experiment

An experiment is a procedure carried out to support, refute, or validate a hypothesis. The video describes a simple experiment where different solutions are prepared and their evaporation rates are observed, providing a practical demonstration of vapor pressure concepts.

💡Observation

Observation is the act of noticing and recording information through the senses. In the video, observations of the amount of condensation on the lids of the glasses containing different solutions are used to infer the relative vapor pressures, showcasing the importance of observation in experimental science.

💡Hypothesis

A hypothesis is a proposed explanation for a phenomenon. The video's script suggests a hypothesis that the addition of solutes to a solvent will affect its vapor pressure, which is then tested through the described experiment.

Highlights

Introduction to the experiment on the reduction of vapor pressure by Melanie, a chemistry education student.

Explanation of vapor pressure reduction due to the presence of a solute in a solvent.

The experiment can be conducted at home using common household items.

List of materials needed for the experiment: three glasses, lids, spoon, water, sugar, salt, and a measuring cup.

Procedure to fill each glass with 100 milliliters of water and add solute (salt or sugar) to two of them.

Observation that the glass with pure water had the most vapor, indicating higher vapor pressure.

The presence of salt or sugar in water reduces the vapor pressure compared to pure water.

The experiment demonstrates the effect of solutes on vapor pressure through observable vapor condensation on glass lids.

Theoretical explanation of why vapor condenses on the lids due to vapor pressure.

Difference in intermolecular forces between pure solvent and solute-solvent mixtures.

The more solute added to a solvent, the lower the vapor pressure and the less water vaporizes.

Animation provided to illustrate the vaporization process and the effect of solutes on vapor pressure.

Comparison of vapor pressure between pure solvent and solution, showing higher pressure in the pure solvent.

Conclusion that the addition of solutes to a solvent results in a decrease in vapor pressure.

Encouragement for viewers to conduct the experiment at home for a better understanding.

Closing remarks with a summary of the learning points and a call to action for home experimentation.