Solutions and Solubility

Question 1

What are solutions?

Answer 1

Solutions are homogenous mixtures of two or more substances.

Question 2

What is the composition of a solution?

Answer 2

Solute+ Solvent

Question 3

What is a solute?

Answer 3

Solids, liquids or gases dissolved in a solvent in small quantities.

Question 4

What is a solvent?

Answer 4

Solids, liquids or gases present in large quantities in which a solute in dissolved.

Question 5

______ solvents are present in the most common solutions.

Answer 5

Liquid

Question 6

What is an aqueous solution?

Answer 6

Solution with water as solvent.

Question 7

Why is water an important solvent?

Answer 7

1. Most important solvent to dissolve inorganic solute.
2. Common pharamceutical solvent.
3. Important biological solvent.
4. Makes around 60% of our body.
5. Largely due to its structure.

Question 8

Give an example of a solution with a gas as a solvent.

Answer 8

Air
Solvent- Nitrogen

Question 9

Give an example of a solution with solid as a solvent.

Answer 9

Alloys
Solvent- Metal

Question 10

What do the properties of liquid solutions depend on?

Answer 10

1. The type of solute added in the solution.
2. The amount of solute added in the solution.

Question 11

What is the difference between clear and colorless solutions?

Answer 11

Clear solutions- Only one state of matter can be deciphered from the solutions. Solute particles are not seen.
Colorless solutions- Absence of color.

Question 12

On what basis are solutions classified into?

Answer 12

1. On the basis on conduction of electricity.
2. On the basis of particle size.
3. On the basis of solubility.

Question 13

What is the difference betwenn electrolytic and non-electrolytic solutions?

Answer 13

Electrolytic solution:
* Conduct electricty
* Solutions of solids, bases and salts.
* Used in hospitals for replacement therapy to treat the imbalance of ions.

Non-electrolytic solution:
* Does not conduct electricity.

Question 14

What are the characteristics of true solutions?

Answer 14

1. Have small particle size.
2. Homogenous.
3. Do not settle over time.
4. Cannot be separated through filtration.
5. Distinguished from pure substances through chemical analysis.
6. Do not scatter light.

Question 15

What are the characteristics of colloids?

Answer 15

1. Particle size of colloids> true solutions (1-1000nm)
2. Not truly homogenous.
3. Does not settle over time.
4. Shows tyndall effect.

Question 16

What are the characteristics of suspensions?

Answer 16

1. Particle diameter> 1000nm
2. Heterogenous (not a true solution, neither a precipitate)
3. Settles over time.
4. Eg. Blood

Question 17

What is the particle diameter of blood?

Answer 17

> 1 micrometer

Question 18

____________ is a way to speed up settling of particles in a suspension.

Answer 18

Centrifugation

Question 19

What are the characteristics of unsaturated solutions?

Answer 19

1. Solute concentration is less than equilibrium solubility.
2. All the solute is dissolved.
3. As the solute is not in equilibrium with the solution yet, there is room for more solute.

Question 20

What are the characteristics of saturated solutions?

Answer 20

1. The solute concentration is equal to equilibrium solubility.
2. All the solute that could be dissolved by the solution at that temperature is dissolved.
3. As the dissolved and undissolved solute are in equilibrium, there is no room for more.

Question 21

What are the characteristics of super-saturated solutions?

Answer 21

1. The solute concentration is way more than equilibrium solubility.
2. All the solute is not dissolved.

Question 22

What is solubility?

Answer 22

Solubility is the ability of the solute to dissolve in the solvent.

Question 23

What are the conditions in our body caused due to undissolved substances?

Answer 23

1. Gout- Accumulation of uric acid crystals in soft tissues, cartilage and tendons
2. Kindney stones- calcium oxalate of calcium phosphate in the urinary tract, bladder, urethra or kidneys.

Question 24

What is hyperuricemia?

Answer 24

High levels of uric acid in the blood.

Question 25

Uric acid is a product of ____________________.

Answer 25

Purine degradation

Question 26

What are three solubility trends?

Answer 26

1. Polarity 2. Temperature 3. Pressure

Question 27

How is ammonia soluble in water?

Answer 27

* Ammonia is a polar solute and water is a polar solvent. * They are soluble because of intermolecular forces. * Partial negative charge and partial positive charges of both molecules interact.

Question 28

Why is oil insoluble in water?

Answer 28

* Oil is a non-polar solute and water is a polar solvent. * Oil has carbon and hydrogen atoms that do not carry any charge. * Water molecules attract themselves but not oil.

Question 29

Why does increase in temperature increase solubility in solutions where the solute is solid or liquid?

Answer 29

Dissolution reuires breaking of intermolecular forces amongst the solute particles and amongst the solvent particles which requires energy. Energy is released in the formation of new intermolecular bonds between solute and solvent molecules.

Question 30

Why does solubility of gases decrease with increase in temperature?

Answer 30

Solubility of gases in liquids is in liquid phase. This is similar to the phenomenon of condensation. As condensation is an exothermic process, increase in temperature decreases solubility.

Question 31

Why is pressure insignificant to the solubility ofliquids and solids in liquids?

Answer 31

Because the volume of liquids and solids stays constant.

Question 32

Why does solubility of gases increase with increase in pressure?

Answer 32

Due to Henry's Law. Henry's Law- Mole fraction of gases dissolved in solution increases with increase in partial pressure of the gas over the solution.

Question 33

How is solubility related to equilibrium?

Answer 33

* When a solute is added to a solvent, it dissolves in it and this continues till the the dissolved and undissolved solute are in equilibrium with eachother. * At this stage the process of dissolution and crystalisation accur at the same rate.

Question 34

What is degree of solubility?

Answer 34

* It is a quantitative measure of solubility. * It is the amount of solute that can be dissolved in a given amount of solvent. * It is achieved by solubility product constant.