The document discusses the solubility of gases in liquids. It defines solubility as the concentration of dissolved gas in equilibrium with pure gas above the solution. Examples given include carbonated beverages with CO2 and ammonia water. The solubility of gases is affected by temperature, pressure, and the nature of the solvent and solute. Specifically, increasing pressure increases solubility by allowing more gas to dissolve, while increasing temperature generally decreases solubility.

1. SOLUBILITY OF GAS IN LIQUIDS
SOLUBILITY PHYSICAL PHARMACEUTICS-I

2. SOLUBILITY OF GAS IN LIQUIDS
SOLUBILITY PHYSICAL PHARMACEUTICS-I

3. SOLUBILITY OF GAS IN LIQUIDS
 Solubility of gas in liquids is the concentration of dissolved
gas in the liquid when it is in equilibrium with the pure
gas above the solution.
 The example of gas in liquid includes effervescent
preparations containing dissolved carbon dioxide,
ammonia water and hydrochloride gas.
 Aerosol products containing nitrogen or carbon dioxide as
propellant are also considered to be solution of gases in
liquids.

4. NH3 IN WATER

5. HCL GAS IN WATER

6. CO2 IN WATER

7. SOLUBILITY OF GAS IN LIQUIDS
 Gas solubility in liquids deals with the concept of gas
dissolving in a solvent.
 For any substance, solubility is the maximum amount of
solute that can be dissolved in a given solvent at a
particular temperature.
 In this case gas is as solute and vehicle liquid is solvent.
 The gas solubility in liquids is greatly affected by
temperature and pressure as well as the nature of the
solute and the solvent.

8. SOLUBILITY OF GAS IN LIQUIDS
 There are many gases that readily dissolve in water, while
there are gases that do not dissolve in water under normal
conditions they required to maintain pressure to dissolve.
 1. Oxygen is only sparingly soluble in water
 2. Ammonia readily dissolves in water.
 3. Carbon dioxide is only water-soluble, when pressure is
maintained.
 After pressure drops the CO2 gas will try to escape to air.
 It is characterised by the bubbles formation of CO2 into water.

9. FACTORS INFLUENCING SOLUBILITY
 1. Temperature
 2. Nature of solvent
 (like dissolves like)
 3. Pressure
 4. pH
 5. Particle size
 6. Crystal structure
 7. Molecular structure
 8. Solute- solvent
interactions
 9. Melting point and
boiling point.
 10. Addition of substituent
 11. Solubilizing agents

10. Factors Affecting on Solubility of gases in liquid
 So many factors affect on solubility but for Solubility of
gases in liquid following two factors mainly consider to
achieve proper solubility or to dissolve gas in liquid
 1. Effect of Pressure:
 Increase in pressure --> Increase in solubility
 2. Effect of Temperature
 Increase in Temperature --> Decrease in solubility

11. 1. Effect of Pressure
 Typically, a gas will increase in solubility
with an increase in pressure.
 The higher the pressure above a liquid,
the more gas that can be dissolved in
that liquid, to a limit of course.
 The solubility of gases depends on the
pressure: an increase in pressure
increases solubility, whereas a decrease
in pressure decreases solubility.

12. 1. Effect of Pressure

13. 1. Effect of Pressure
 The higher the pressure above a liquid, the
more gas that can be dissolved in that liquid,
to a limit of course.
 The solubility of gases depends on the
pressure:
 An increase in pressure increases solubility,
 A decrease in pressure decreases solubility.

14. 1. Effect of Pressure
 The solubility of a gas in a liquid is directly proportional to the
partial pressure of the gas present above the surface of liquid or
solution.
 The most general way of using Henry's Law is that the partial
pressure of a gas above a solution is proportional to the mole
fraction of the gas in the solution.
 P = KHx Where,
 P = partial pressure of the gas
 x = mole fraction of the gas in solution
 KH = Henry’s law constant

15. 1. Effect of Pressure
 Henry's Law relates the
solubility of a gas over a
solution based on the
factors of temperature,
volume and pressure.

16. 1. Effect of Pressure
 Henry's Law relates
the solubility of a gas
over a solution based
on the factors of
temperature, volume
and pressure.

17. 2. Effect of Temperature
For all gases,
solubility
decreases as the
temperature of
the solution
increases.

18. 2. Effect of Temperature
For all gases,
solubility
decreases as the
temperature of
the solution
increases.