What Is The Freezing Point Of Sodium Chloride Dissolved In Acetic Acid With A Freezing Point Depression (FPD) Of 11.9°C?

Introduction

The freezing point depression (FPD) is a phenomenon that occurs when a solute is dissolved in a solvent, causing the freezing point of the solution to decrease. This concept is widely used in various fields, including chemistry, physics, and engineering. In this article, we will discuss the freezing point of sodium chloride dissolved in acetic acid with a freezing point depression (FPD) of 11.9°C.

Understanding Freezing Point Depression

Freezing point depression is a colligative property, which means that it depends on the number of particles (molecules or ions) present in the solution, rather than their identity. When a solute is dissolved in a solvent, it breaks down into smaller particles, which then interact with the solvent molecules. This interaction disrupts the formation of a crystal lattice structure, making it more difficult for the solvent to freeze.

Theoretical Background

The freezing point depression of a solution can be calculated using the following equation:

ΔTf = Kf × m

where ΔTf is the freezing point depression, Kf is the freezing point depression constant, and m is the molality of the solution.

For sodium chloride (NaCl) dissolved in acetic acid (CH3COOH), the freezing point depression constant (Kf) is 1.86 K kg/mol. The molality of the solution can be calculated using the following equation:

m = moles of solute / kg of solvent

Calculating the Freezing Point of Sodium Chloride in Acetic Acid

To calculate the freezing point of sodium chloride dissolved in acetic acid with a freezing point depression (FPD) of 11.9°C, we need to know the molality of the solution. Let's assume that we have 1 mole of sodium chloride dissolved in 1 kg of acetic acid.

The molality of the solution is:

m = 1 mole / 1 kg = 1 mol/kg

Now, we can calculate the freezing point depression using the equation:

ΔTf = Kf × m = 1.86 K kg/mol × 1 mol/kg = 1.86 K

The freezing point of the solution is:

Tf = Tf0 - ΔTf = 273.15 K - 1.86 K = 271.29 K

Converting the Freezing Point to Celsius

To convert the freezing point from Kelvin to Celsius, we can use the following equation:

Tc = Tf - 273.15

Substituting the value of Tf, we get:

Tc = 271.29 K - 273.15 = -1.86°C

Conclusion

In conclusion, the freezing point of sodium chloride dissolved in acetic acid with a freezing point depression (FPD) of 11.9°C is -1.86°C. This value can be calculated using the freezing point depression equation and the molality of the solution.

Factors Affecting Freezing Point Depression

There are several factors that can affect the freezing point depression of a solution, including:

• Concentration of the solute: The freezing point depression increases with increasing concentration of the solute.
• Temperature: The freezing point depression is independent of temperature.
• Identity of the solute: The freezing point depression depends on the identity of the solute, but not on its concentration.
• Identity of the solvent: The freezing point depression depends on the identity of the solvent, but not on its concentration.

Applications of Freezing Point Depression

Freezing point depression has several applications in various fields, including:

• Chemical engineering: Freezing point depression is used to determine the concentration of a solute in a solution.
• Biotechnology: Freezing point depression is used to preserve biological samples.
• Food industry: Freezing point depression is used to determine the concentration of sugar in a solution.
• Pharmaceutical industry: Freezing point depression is used to determine the concentration of a solute in a solution.

Experimental Methods for Measuring Freezing Point Depression

There are several experimental methods for measuring freezing point depression, including:

• Thermocouple method: This method involves using a thermocouple to measure the temperature of the solution as it freezes.
• Differential scanning calorimetry (DSC) method: This method involves using a DSC instrument to measure the heat flow into or out of the solution as it freezes.
• Freezing point depression apparatus: This method involves using a specialized apparatus to measure the freezing point depression of a solution.

Conclusion

In conclusion, the freezing point of sodium chloride dissolved in acetic acid with a freezing point depression (FPD) of 11.9°C is -1.86°C. This value can be calculated using the freezing point depression equation and the molality of the solution. Freezing point depression has several applications in various fields, including chemical engineering, biotechnology, food industry, and pharmaceutical industry. Experimental methods for measuring freezing point depression include thermocouple method, DSC method, and freezing point depression apparatus.

Q: What is freezing point depression?

A: Freezing point depression is a phenomenon that occurs when a solute is dissolved in a solvent, causing the freezing point of the solution to decrease.

Q: What are the factors that affect freezing point depression?

A: The factors that affect freezing point depression include concentration of the solute, temperature, identity of the solute, and identity of the solvent.

Q: How is freezing point depression calculated?

A: Freezing point depression is calculated using the following equation:

ΔTf = Kf × m

where ΔTf is the freezing point depression, Kf is the freezing point depression constant, and m is the molality of the solution.

Q: What is the freezing point depression constant (Kf)?

A: The freezing point depression constant (Kf) is a constant that depends on the identity of the solvent and the solute.

Q: How is the molality of a solution calculated?

A: The molality of a solution is calculated using the following equation:

m = moles of solute / kg of solvent

Q: What is the difference between freezing point depression and boiling point elevation?

A: Freezing point depression is the decrease in the freezing point of a solution, while boiling point elevation is the increase in the boiling point of a solution.

Q: Can freezing point depression be used to determine the concentration of a solute in a solution?

A: Yes, freezing point depression can be used to determine the concentration of a solute in a solution.

Q: What are the applications of freezing point depression?

A: The applications of freezing point depression include chemical engineering, biotechnology, food industry, and pharmaceutical industry.

Q: How is freezing point depression measured experimentally?

A: Freezing point depression is measured experimentally using thermocouple method, DSC method, and freezing point depression apparatus.

Q: What are the limitations of freezing point depression?

A: The limitations of freezing point depression include the need for a known freezing point depression constant (Kf) and the potential for errors in measurement.

Q: Can freezing point depression be used to determine the identity of a solute in a solution?

A: No, freezing point depression cannot be used to determine the identity of a solute in a solution.

Q: What is the relationship between freezing point depression and the number of particles in a solution?

A: The freezing point depression is directly proportional to the number of particles in a solution.

Q: Can freezing point depression be used to determine the concentration of a solute in a solution at high temperatures?

A: No, freezing point depression cannot be used to determine the concentration of a solute in a solution at high temperatures.

Q: What is the significance of freezing point depression in everyday life?

A: Freezing point depression has significant implications in everyday life, including the preservation of food, the production of pharmaceuticals, and the development of new materials.

Q: Can freezing point depression be used to determine the purity of a solvent?

A: Yes, freezing point depression can be used to determine the purity of a solvent.

Q: What are the advantages of using freezing point depression in chemical engineering?

A: The advantages of using freezing point depression in chemical engineering include the ability to determine the concentration of a solute in a solution, the ability to determine the identity of a solvent, and the ability to determine the purity of a solvent.

Q: Can freezing point depression be used to determine the concentration of a solute in a solution at low temperatures?

A: Yes, freezing point depression can be used to determine the concentration of a solute in a solution at low temperatures.

Q: What is the relationship between freezing point depression and the solubility of a solute in a solvent?

A: The freezing point depression is directly proportional to the solubility of a solute in a solvent.

Q: Can freezing point depression be used to determine the identity of a solvent in a solution?

A: Yes, freezing point depression can be used to determine the identity of a solvent in a solution.

Q: What are the limitations of using freezing point depression in biotechnology?

A: The limitations of using freezing point depression in biotechnology include the need for a known freezing point depression constant (Kf) and the potential for errors in measurement.

Q: Can freezing point depression be used to determine the concentration of a solute in a solution at high pressures?

A: No, freezing point depression cannot be used to determine the concentration of a solute in a solution at high pressures.

Q: What is the significance of freezing point depression in the food industry?

A: Freezing point depression has significant implications in the food industry, including the preservation of food, the production of frozen foods, and the development of new food products.

Q: Can freezing point depression be used to determine the identity of a solute in a solution at low temperatures?

A: Yes, freezing point depression can be used to determine the identity of a solute in a solution at low temperatures.

Q: What are the advantages of using freezing point depression in pharmaceutical industry?

A: The advantages of using freezing point depression in pharmaceutical industry include the ability to determine the concentration of a solute in a solution, the ability to determine the identity of a solvent, and the ability to determine the purity of a solvent.

Q: Can freezing point depression be used to determine the concentration of a solute in a solution at high temperatures and high pressures?

A: No, freezing point depression cannot be used to determine the concentration of a solute in a solution at high temperatures and high pressures.