Solutions

What is a Solution?

Solutions – Definition: A solution is a homogeneous mixture of two or more substances. The substances are dissolved in a solvent to form a solution. The solvent is the substance that is in the greatest quantity. The solutes are the substances that are in the lesser quantity. Solutions can be liquids, gases, or solids.

S.NO	CONTENT
1.	INTRODUCTION
2.	SOLUTE
3.	SOLVENT
4.	PROPERTIES OF SOLUTION
5.	TYPES OF SOLUTIONS ON QUANTITY OF SOLUTE
6.	TYPES OD SOLUTIONS ON THE BASIS OF SOLVENT
7.	MOLARITY AND MOLALITY
8.	SOLUBILITY
9.	HENRY’S LAW

Solutions Consist of -Solute and Solvent

A solute is a substance that is dissolved in a solvent to create a solution. The solvent is the liquid in which the solute is dissolved. The solution is the mixture of the solute and also solvent.

Solute

In chemistry, a solute is a substance that is dissolved in a solvent to form a solution. The solvent is usually a liquid, but solids and gases can also act as solvents.

Solvent -based coatings

• Solvent-based coatings are coatings that are applied to a surface using a solvent, such as a lacquer or an enamel.
• The solvent evaporates as the coating dries, leaving the film of coating behind.
• Solvent-based coatings are usually less durable than water-based coatings, but they can produce a more glossy finish.
• Properties of a Solution
• A solution is a homogeneous mixture of two or more substances.
• The solvent is the substance that is present in the greatest quantity.
• The solute is the substance that is present in the smallest quantity.
• The solution has the same properties as the solvent.
• The solution is able to dissolve other substances.

Types of Solutions Based on Quantity of Solute

A solution is a type of mixture in which a solvent (usually water) dissolves one or more solutes to form a homogeneous mixture.

There are three types of solutions based on the quantity of solute:

1. Solution
2. Suspension
3. Colloid

Unsaturated Solution

A solution that contains at least one molecule of a solute that is not fully surrounded by solvent molecules is called an unsaturated solution. If a solvent molecule is added to an unsaturated solution, the solute will be surrounded by more solvent molecules and the solution will become saturated.

Saturated Solution

A saturated solution is a solution that has reached its maximum concentration. Adding more of the solute to a saturated solution will not cause the solution to become any more concentrated.

Supersaturated Solution

A supersaturated solution is a solution that contains more solute than it is theoretically supposed to contain at that given temperature and pressure.

Types of Solutions Based on the amount of solvent added

• Aqueous solutions are solutions in which the solvent is water.
• Non-aqueous solutions are solutions in which the solvent is not water.

Concentrated Solution

A concentrated solution is a solution in which a large amount of solute is dissolved in a small amount of solvent. When a concentrated solution is diluted, the solute will spread out evenly in the solvent.

Dilute Solution

The concentration of a solution is the amount of solute (substance dissolved in a solvent) dissolved in a given amount of solvent. Therefore the concentration is usually expressed in terms of molarity (moles of solute per liter of solvent).

A dilute solution is a solution in which the concentration of the solute is low.

Expressing Concentrations of Solutions

• In chemistry, concentrations are usually expressed in molarity (M), which is the number of moles of solute per liter of solution.
• Another common concentration unit is molality (m), which is the number of moles of solute per kilogram of solvent.

Mass Percentage (w/w)

• 25%
• 100%

Volume Percentage (V/V)

The volume percentage (V/V) is the ratio of the volume of a substance to the total volume of the mixture.

formula

V/V = (Volume of Substance) / (Volume of Mixture)

Mass by Volume Percentage (w/V)

The weight by volume percentage of a substance is the weight of the substance divided by the volume of the substance, multiplied by 100.

Parts per Million (ppm)

A measure of the concentration of a particular component in a given mixture. For example, in air, the concentration of carbon dioxide is about 400 ppm.

Mole Fraction (x)

The mole fraction is the number of moles of a component divided by the total number of moles in a mixture.

formula_1

where “x” is the mole fraction of component “A”, “n” is the number of moles of component “A”, and also “N” is the total number of moles in the mixture.

Molarity (M) – Number of Moles of Solute Dissolved in One Liter of Solution.

Moles (mol) – The Number of Molecules in a Substance.

Normality (N) – The Number of Moles of Ions in a Solution.

Molality (m) – Number of Moles of Solute in One KG of the Solvent.

• Mole (mol) – The SI unit for amount of substance. It is the amount of a substance that contains as many elementary entities as there are atoms in 12 grams of carbon-12.
• Mole Fraction (x) – The mole fraction of a component in a mixture is the number of moles of that component divided by the total number of moles in the mixture.
• Molecular Weight (MW) – The molecular weight of a substance is the sum of the atomic weights of the atoms in the molecule.
• Normality (N) – The normality of a solution is the number of equivalents of solute per liter of solution.

Solubility

Insoluble in water.

Slightly soluble in alcohol.

Chemical Formula

C 8 H 10 O

Molecular Weight

138.17

Factors that Affect the Solubility of a Substance

The solubility of a substance is affected by a number of factors, including:

• The temperature of the solvent
• The nature of the solvent
• The chemical nature of the solute
• The concentration of the solute
• The presence of other solutes
• Also the pressure of the system

Solubility of a Solid in a Liquid

The solubility of a solid in a liquid is the maximum amount of solid that can dissolve in a given quantity of liquid. However the solubility of a solid in a liquid is determined by the chemical properties of the solid and the liquid and the physical properties of the solid and the liquid.

Le Chatelier’s Principal

The Chatelier’s Principal is a theorem in classical mechanics that states that the time rate of change of momentum is equal to the force applied. However this theorem is named after Jean Baptiste Joseph Fourier’s student, Jacques Charles Antoine Chathelier.

The theorem is also called the principle of impulse and momentum.

Solubility of a Gas in a Liquid

The solubility of a gas in a liquid is the amount of gas that will dissolve in a liquid at a given temperature. However the higher the temperature, the more gas will dissolve in the liquid.

Henry’s Law

After a period of time, the concentration of a gas in a closed container will reach equilibrium with the concentration of the gas in the surrounding atmosphere.

Another form of Henry’s law is

k = (P1/T1) (P2/T2)

This equation states that the rate of a reaction is proportional to the product of the concentrations of the reactants.

Applications of Henry’s law

Some specific applications of Henry’s law are as follows:

1. In the brewing and winemaking industries, CO 2 used to carbonate beverages. The concentration of CO 2 in the beverage controlled by Henry’s law.
2. In the food industry, CO 2 used to carbonate foods such as cola and sparkling wine. The concentration of CO 2 in the food controlled by Henry’s law.
3. In the pharmaceutical industry, CO 2 used to carbonate pills. Therefore the concentration of CO 2 in the pill controlled by Henry’s law.

Raoult’s Law

• The vapor pressure of a liquid is a function of the temperature and also the composition of the liquid.
• Vapor pressure of a pure liquid is a function of the temperature.
• The vapor pressure of a solution is a function of the temperature and also the composition of the solution.

Total Pressure

The total pressure is the sum of the gas pressure and also the atmospheric pressure.

formula_1

Where:

• P is the total pressure
• P_atm is the atmospheric pressure
• ALso P_gas is the gas pressure

Raoult’s Law can Also Stated as Follows:

The vapor pressure of a solution is directly proportional to the mole fraction of the solvent in the solution.

Ideal Solutions

There is no one perfect solution to the problem of gun violence, but there are some measures that could help to reduce the number of gun-related deaths and injuries.

Some measures that could help to reduce gun violence include:

• Strengthening gun control laws, including background checks and also waiting periods
• Increasing funding for mental health programs
• Banning assault weapons and high-capacity magazines
• Improving school safety measures
• Encouraging responsible gun ownership

Non – Ideal Solution

Non-ideal solutions are not always the best option, but they are better than no solution at all. In some cases, a non-ideal solution may be the only option available.

Relative Lowering of Vapor Pressure

A decrease in the vapor pressure of a liquid at a given temperature.

For a Highly Diluted Solution

• For a 1% solution, use 1 part of the solute to 99 parts of the solvent.
• Also for a 0.1% solution, use 1 part of the solute to 99 parts of the solvent.
• For a 0.01% solution, use 1 part of the solute to 99 parts of the solvent.

Elevation of Boiling Point

• The boiling point of a substance is the temperature at which the vapor pressure of the liquid is equal to the atmospheric pressure.
• Therefore the boiling point of a substance is increased when the atmospheric pressure is increased.

Depression of Freezing Point

• The depression of freezing point is the decrease in the freezing point of a solvent caused by the addition of a solute.
• When a solute added to a solvent, the molecules of the solute interact with the molecules of the solvent. This interaction can disrupt the orderly arrangement of the solvent molecules, causing them to come into closer contact with one another. This increased contact between solvent molecules can lower the freezing point of the solvent.
• The depression of freezing point increases as the concentration of the solute increases. For a given solvent, the depression of freezing point increases as the size of the solute molecule increases. The depression of freezing point also affected by the type of solute molecule. Ionic solutes cause a greater depression of freezing point than non-ionic solutes.

Freezing Point

However the freezing point is the temperature at which a liquid turns into a solid.

Depression in Freezing Point

Freezing point depression is a colligative property of a solvent that occurs when a solute dissolved in it. The addition of a solute to a solvent decreases the solvent’s freezing point. This phenomenon used in industrial processes to produce ice cream and other frozen foods. It also used in the production of certain medications.

Osmosis and Osmotic Pressure

The process of osmosis is the movement of water molecules from a region of high water concentration to a region of low water concentration through a semi-permeable membrane. The water molecules will continue to move until the concentration is equal on both sides of the membrane.

The force that drives osmosis called osmotic pressure. Therefore the higher the concentration of water molecules on one side of the membrane, the greater the osmotic pressure. This pressure can measured in units of atmospheres (atm) or pounds per square inch (psi).

For more read Types of Solutions – Solution in Chemistry