Chemistry REVISION OF SOLUTIONS
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### INTRODUCTION

•color{green} ("Homogeneous Solutions") : These are mixtures of two or more than two components. These have uniform composition and properties throughout the mixture.

•color{green}("Solvent") : The component that is present in the largest quantity is known as solvent. Solvent determines the physical state of solution.

•color{green}("Solute") : One or more components present in the solution other than solvent are called solutes.

### CONCENTRATION TERMS

•color{green} ("Mass percentage") text(Mass of the component in the solution)/text(Total mass of the solution) xx 100.

•color{green} ("Volume percentage"): text(Volume of the component)/ text(Total volume of solution) xx 100.

•color{green} ("Mass by Volume percentage"): It is the mass of solute dissolved in 100 mL of the solution.

•color{green} ("Parts per million"): text(Number of parts of the component)/text(Total number of parts of all components of the solution) xx 10^6.

•color{green}("Mole fraction") :text(Number of moles of the component)/text(Total number of moles of all the components).

•color{green}("Molarity") : It is defined as number of moles of solute dissolved in one litre (or one cubic decimetre) of solution.
text(Moles of solute)/ text(Volume of solution in litre).

•color{green}("Molality") : It is defined as the number of moles of the solute per kilogram (kg) of the solvent and is expressed as
text(Moles of solute)/text(Mass of solvent in kg).

### Effect of temperature on solubility of solids

•color{green}("Solubility") : It's the maximum amount of a substance that can be dissolved in a specified amount of solvent.

• color{green}("Dissolution") : When a solid solute is added to the solvent, some solute dissolves and its concentration increases in solution. This process is known as dissolution.

• color{Green}("Crystallisation") : Some solute particles in solution collide with the solid solute particles and get separated out of solution. This process is known as crystallisation.

•color{green}("Saturated Solution") : A solution in which no more solute can be dissolved at the same temperature and pressure is called a saturated solution.

• color{green}("Unsaturated Solution") : An unsaturated solution is one in which more solute can be dissolved at the same temperature.

### How pressure affects solubility of gases

• color{green}("Henry's law") : The partial pressure of the gas in vapour phase (p) is proportional to the mole fraction of the gas (x) in the solution” and is expressed as :

color{green}(p = K_H x)

Here color{geen}(K_H) is the Henry’s law constant.

### Raoult's law

•color{green}("Raoult's law") : For a solution of volatile liquids, the partial vapour pressure of each component in the solution is directly proportional to its mole fraction.

•color{green}("Vapour pressure"): Under equilibrium conditions the pressure exerted by the vapours of the liquid over the liquid phase is called vapour pressure .

### Depression of freezing point

•color{green}("Freezing point") : The freezing point of a substance may be defined as the temperature at which the vapour pressure of the substance in its liquid phase is equal to its vapour pressure in the solid phase.

### Osmosis

•color{green}("Osmosis") : The osmosis may be defined as the process of passage of solvent from solution of lower concentration into solution of higher concentration.

•color{green}("Osmotic pressure"):The flow of the solvent from its side to solution side across a semipermeable membrane can be stopped if some extra pressure is applied on the solution. This pressure that just stops the flow of solvent is called osmotic pressure of the solution.

### Isotonic,hypertonic,hypotonic solution

•color{green}("Isotonic solution") :The solutions of different compounds which have same osmotic pressure at a temperature.

•color{green}("Hpertonic solution") :If a solution has more osmotic pressure than some other solution is called hypertonic solution.

•color{green}("Hypotonic solution") :If a solution has less osmotic pressure than some other solution is called hypotonic solution.

### Reverse osmosis

•color{green}("Reverse osmosis") :The direction of osmosis can be reversed if a pressure larger than the osmotic pressure is applied to the solution side. Now the pure solvent flows out of the solution through the semi permeable membrane. This phenomenon is called reverse osmosis.

### Abnormal molar mass

•color{green}("Abnormal Mass") :Such a molar mass that is either lower or higher than the expected or normal value is called as abnormal molar mass.

•color{green}("Colligative properties") :These are the properties which depend on the number of solute particles irrespective of their nature relative to the total number of particles present in the solution (colligative : from Latin : co means together, ligare means to bind).