Solubility of Gases in Liquids

The percentage of oxygen in air is about $21\%$. But the oxygen cylinder meant to be carried by deep sea divers contains about $4\%$ oxygen. Why is there a difference in the percentage of oxygen? 

Dissolution of a solid X in water is exothermic. How does its solubility change with temperature?

Assume that the solubilities of $\mathrm{KCl}$ and ${\mathrm{KNO}}_3$ are the same at a given temperature. A saturated solution of $\mathrm{KCl}$ is taken at that temperature and solid ${\mathrm{AgNO}}_3$ is added to it. The amount of ${\mathrm{AgNO}}_3$ added is such that all the ions present in the solution get precipitated as $\mathrm{AgCl}$. What will be the state of the solution in terms of saturation? 
 

Two saturated aqueous solutions A and B using the same solute are prepared at $25°\mathrm{C}$ and $40°\mathrm{C}$, respectively. The densities of A and B are $1200 \mathrm{g}/\mathrm{l}$ and $1300 \mathrm{g}/\mathrm{l}$ at the given temperatures $600 \mathrm{g}$ of solution A is heated to $40°\mathrm{C}$ from $25°\mathrm{C}$. $\mathrm{x} \mathrm{g}$ of solute is added to it in order to saturate it. Then this solution is cooled to $15°\mathrm{C}$ and $75 \mathrm{g}$ solute is precipitated. Consider the density of water as $1 \mathrm{g}/\mathrm{cc}$ at all the given temperatures and the addition of solute in water does not alter the volume of the solution. Calculate the density of the solution in $\mathrm{g}/\mathrm{l}$ at $15°\mathrm{C}$. 

Two saturated aqueous solutions A and B using the same solute are prepared at $25°\mathrm{C}$ and $40°\mathrm{C}$, respectively. The densities of A and B are $1200 \mathrm{g}/\mathrm{l}$ and $1300 \mathrm{g}/\mathrm{l}$ at the given temperatures $600 \mathrm{g}$ of solution A is heated to $40°\mathrm{C}$ from $25°\mathrm{C}$. $\mathrm{x} \mathrm{g}$ of solute is added to it in order to saturate it. Then this solution is cooled to $15°\mathrm{C}$ and $75 \mathrm{g}$ solute is precipitated. Consider the density of water as $1 \mathrm{g}/\mathrm{cc}$ at all the given temperatures and the addition of solute in water does not alter the volume of the solution. Calculate $\mathrm{x}$. 

Two saturated aqueous solutions A and B using the same solute are prepared at $25°\mathrm{C}$ and $40°\mathrm{C}$, respectively. The densities of A and B are $1200 \mathrm{g}/\mathrm{l}$ and $1300 \mathrm{g}/\mathrm{l}$ at the given temperatures $600 \mathrm{g}$ of solution A is heated to $40°\mathrm{C}$ from $25°\mathrm{C}$. $\mathrm{x} \mathrm{g}$ of solute is added to it in order to saturate it. Then this solution is cooled to $15°\mathrm{C}$ and $75 \mathrm{g}$ solute is precipitated. Consider the density of water as $1 \mathrm{g}/\mathrm{cc}$ at all the given temperatures and the addition of solute in water does not alter the volume of the solution. 

Calculate the solubility of the solute at $25°\mathrm{C}$ and $40°\mathrm{C}$. 

 The solubility of a salt $\mathrm{X}$ is $30$ at $25°\mathrm{C}$. If its relative molecular mass is $35 \mathrm{amu}$, calculate the number of molecules of solute present in $260 \mathrm{g}$ of saturated solution.

Observe the given curves. Saturated solutions of A and B are cooled from $80°\mathrm{C}$ to $40°\mathrm{C}$. Which of the above curves is associated with the formation of more amount of precipitate? 

The solubility of a solute is $35$ at $60°\mathrm{C}$ and $25$ to $30°\mathrm{C}$. If $200 \mathrm{g}$ of solvent is made to saturate with the solute at $60°\mathrm{C}$, what is the amount of precipitate formed at $30°\mathrm{C}$? 

Calculate the solubility of the solute, if $\mathrm{x} \mathrm{g}$ of solute is present in $\mathrm{y} \mathrm{g}$ of saturated solution at a given temperature. 

Solubility of a salt in water is $22$ at $25°\mathrm{C}$. Calculate the amount of the salt required to saturate $500 \mathrm{g}$ water at $25°\mathrm{C}$. 

Select the appropriate option for the following statements:
Statement $1$: In concentrated solution, the molecular mass of the solute is unusual.
Statement $2$: In concentrated solutions intermolecular attraction between molecules is strong.

Suman took two glasses of water from a water filter. She cools one glass in a fridge and warms the other glass on a stove.

Which glass of water will hold more dissolved oxygen?

Explain using Henry's law?

In which solution solubility of$\mathrm{AgCl}$is less than that in pure water? 

Non polar compounds soluble in polar solvent.

How many grams of carbon dioxide gas is dissolved in a $1 \mathrm{L}$ bottle of carbonated water if the manufacturer uses a pressure of $2.4 \mathrm{atm}$ in the bottling process at $25°\mathrm{C}$?
Given: ${\mathrm{K}}_{\mathrm{H}}$ of ${\mathrm{CO}}_2$ in water $= 29.76 \mathrm{atm}/(\mathrm{mol}/\mathrm{L})$ at $25°\mathrm{C}$.

Solubility curve of a hydrated salt in water with temperature is given. The curve indicates that the solution process is

Solubility of a gas in al liquid increases with

Henry's law is valid for

A) Ammonia gas dissolution in water

B) ${\mathrm{O}}_2$ gas dissolution in unsaturated blood

C) ${\mathrm{O}}_2$ dissolution in water

D) ${\mathrm{CO}}_2$ dissolution in water