Equilibrium (nb)

Question 1

Ice and Water are kept in an insulated thermos flask. What will happen?

Answer 1

• Mass of ice and water do not change with time
• Temp remains constant
• Molecules of water collide against ice and stick to the ice molecules, some molecules of ice escape into the liq phase. Both the opposing process occur simultaneously with the same rate.
• Rate of melting of ice <-> rate of freezing of water

Question 2

NMP and NFP

Answer 2

For Pure substance at atm pressure the temperature at which the solid and liq phases are at eqbm

Question 3

NBP

Answer 3

For any pure liq at atm pressure the temp at which the liq and vapour are at eqbm.

Question 4

LIq vapour eqbm

Answer 4

In a glass speaker attached with a manometer, drying agent and hydroscarsian chloride is used to remove the moisture in the glass speaker then a petri dish with the water is kept inside of last speaker, the water gets evaporated thus, pressure develops and mercury level increases. Then the water vapor condenses into liquid at a particular point of time first up the rate of condensation is equal to the rate of evaporation and the mercury level becomes a constant.
- Vapor pressure increases with temperature.
- The liquid which has a higher vapor pressure is more volatile that is they have a low boiling point.

Question 5

Solid Vapour eqbm

Answer 5

I already kept in a box starts to sublime, the vapor fills a box the color starts to intensify from light to dark purple a stage comes when the vapor reaches a constant the . rate of sublimation a solid iodine to iodine vapors is equal to the rate of condensation of vapor iodine to solid iodine.

Question 6

Eqbm in phy processes

Answer 6

1. S- L
2. L-V
3. S-V

Question 7

Dynamic nature of eqbm

Answer 7

Some radioactive sugar is added into the saturated solution of non radioactive sugar. Sometimes, radioactivity is observed in both solid sugar and solution sugar due to the dynamic nature of equilibrium, there is exchange between radioactive and non radioactive sugar molecules.

Question 8

Henry’s Law

Answer 8

It states that the mass of gas dissolved in a given mass of solvent at any temperature is proportional to the partial pressure of the gas above the solvent.
Eg: - When soda contains CO2 in Gaseous State is in equilibrium with CO2 in solution there is a difference in solubility of CO2 at different pressures.

Question 9

General characteristics of equilibrium involving chemical processes.

Answer 9

• Equilibrium is possible only in a closed system at a given temperature
• both the opposing process occur at the same rate and there is dynamic stable condition
• All measurable properties of the system remains constant.

Question 10

Mathematical expression of the thermodynamical view of equilibrium

Answer 10

Delta G = Delta G 0 + RT ln Q
At eqbm
delta G = 0 and Q = Kc
0 = Delta G 0 + RT lnK
lnK = -delta G 0/ RT
taking anti log on both sides
K = e (-delta G / RT)