⚗️ Unit 1 - Chapter 11: Solubility & Colloids (Flashcards)

Solutions

A homogenous mixture of two or more substances

Solvent

A dissolving medium in a solution; present in the largest quantity

Solute

Species dissolved in the solution; present in the smallest amount

Alloys

Solid solutions of one metal dissolved in another

Solution traits

1. Homogeneous after the solution is mixed

2. Physical state = physical state of solvent

3. Dispersed on a molecular scale; it consists of a mixture of separated solute particles (molecules, atoms, and/or ions) each closely surrounded by solvent species.

4. Dissolved solute in a solution will not settle out or separate from the solvent.

5. The solute's concentration can be varied continuously

Spontaneous process

A process that occurs under specified conditions without requiring energy from an external source.

Conditions that favor spontaneous formation solution

1. Decrease in the internal energy of the system (exothermic change)

2. Increased dispersal of matter in the system (increase in the entropy of the system)

Spontaneous process

A process that occurs under specified conditions without requiring energy from an external source.

Conditions that favor spontaneous formation solution:

1. Decrease in the internal energy of the system (exothermic change)
2. Increased dispersal of matter in the system (increase in the entropy of the system)

Ideal solution

A solution in which intermolecular force strength between components is the same as the separated components' intermolecular force strength

Types of intermolecular forces relevant to the dissolution process

1. Solute-solute
2. Solvent-solvent
3. Solute-solvent

The formation of a solution may be viewed as a stepwise process in which:

1. Energy is consumed to break solute-solute and solvent-solvent attractions (endothermic processes)
2. Energy is released to form solute-solvent attractions (exothermic process)

Electrolytes

Substances that undergo physical/chemical changes to yield ions when dissolved

Water & other polar molecules are attracted to ions in ionic compounds via ______ attraction

ion-dipole

Dissociation

Occurs when ionic compounds are completely separated and are surrounded by water molecules

Miscible

Two liquids that mix in all proportions

Imisicble

Two liquids that do not mix

Partially miscible

Two liquids that mix to some extent

Polar molecules can dissolve in water due to ______________ between solvent and solute molecules

dipole-dipole attraction

Strong electrolytes

Substances in which the physical and chemical process that generates ions is 100% efficient

Strong electrolytes have ___________ due to the large number of atoms produced

high conductivity

Weak electrolytes

Substances that partially dissociates to yield a solution

Weak electrolytes have ______________ due to the small quantity of ions produced

low conductivity

Nonelectrolytes

Substances that do not dissociate to yield a solution

Solubility

Maximum concentration of solute that can be achieved under given conditions

Saturated solution

Solution that contains the maximum quantity of solute

Unsaturated solution

Solution that contains less than the maximum quantity of solute

Supersaturated solution

Solutions where the quantity of solute exceeds the solutions' solubility

Factors that affect liquid/gas solubility

1. Temperature
2. Vapor pressure above solvent

How does temperature affects liquid/gas solubility

The higher temperature, higher solubility of gas solute

How pressure above a liquid affects liquid/gas solubility

The higher pressure above the liquid, higher solubility of gas

Henry's law equation

P_g = kC_g

Colligative properties

Properties of a solution that differ from the properties of the pure solute or solvent

Colligative properties include:

1. Vapor pressure lowering
2. Boiling point elevation
3. Freezing point depression
4. Osmotic pressure

Boiling point

Temperature that which a liquid's vapor pressure is equal to atmospheric pressure

Boiling point elevation

Addition of a nonvolatile solute that decreases water pressure, and increases a pure solvent's boiling point

Boiling point elevation equation

\Delta T_b = iK_bm

What the variables in the boiling point elevation equation (\Delta T_b) represent

\Delta T_b represents boiling point elevation, i represents van't Hoff's constant, K_b is the boiling point elevation constant, m is the molality of all soluble species

Freezing point

The temperature where a liquid becomes solid

Freezing point depression equation

\Delta T_f = iK_fm

What the variables in the freezing point depression equation (\Delta T_f) represent

\Delta T_f represents freezing point depression i represents van't Hoff's constant, K_f is the freezing point depression constant and m is the molality of all solute species

How do you calculate a liquid's new boiling point after finding out \Delta T_b?

Add \Delta T_b to the boiling point of the solvent

How you calculate a liquid's new freezing point after finding out \Delta T_f

Subtract \Delta T_f to the freezing point of the solvent

Mole fraction equation

\text{Mole fraction }(X_{component})= \frac{\text{moles of component}}{\text{total moles of all components}}

Molarity (M)

ratio of moles of solute to litres of solution

Molarity equation

\text{Molarity} = \frac{\text{moles of solute}}{\text{litres of solution}}

Molality equation

\text{Molality (m)} = \frac{\text{moles of solute}}{\text{kg of solvent}}

Equilibrium vapor pressure (liquid)

Pressure exerted by a liquid's gaseous phase when vaporization and condensation occur at equal rates

What do the variables in Raoult's law (P_{solution}) represent?

P_{solution} is the partial pressure exerted by the solution, X_{solvent} is the mole fraction of solvent in the solution, and P^*_{solvent} is the vapor pressure of the pure solvent

Distillation

Separation technique that uses differences in vapor pressure to separate multiple volatile liquids in a solution via selective vaporization.

Boiling point

Temperature at which a liquid's vapor pressure is equal to atmospheric pressure.

Boiling point elevation

Addition of a nonvolatile solute that decreases water pressure, and increases a pure solvent's boiling point

Boiling point elevation equation

\Delta T_b = iK_bm

What the variables in the boiling point elevation equation (\Delta T_b) represent

\Delta T_b represents boiling point elevation, i represents van't Hoff's constant, K_b is the boiling point elevation constant, m is the molality of all soluble species

Freezing point depression

Occurs when the addition of a nonvolatile solute separates the solvent molecules, decreasing the freezing point of the pure solvent

How do you calculate a liquid's new boiling point after finding out \Delta T_b?

Add \Delta T_b to the boiling point of the solvent

How you can calculate a liquid's new freezing point after finding out \Delta T_f

Subtract \Delta T_f to the freezing point of the solvent

Semipermeable membranes

Materials that allow select molecules or ions to pass through of a certain size, shape or other factor

For a semipermeable membrane that only allows solvent
molecules to permeate, solvent molecules will diffuse
across the membrane in both directions at ______ ______.

equal rates

If the concentration of solvent is different on either side of the semipermeable membrane, solvent molecules diffuse from the _____ side of solvent concentration toward the ______ side of solvent concentration to equalize solvent concentration.

higher, lower

Osmosis

Diffusion of molecules from a high to low concentration across a partially permeable membrane

Osmotic pressure

Hydrostatic pressure value at an equal rate of solvent transfer across a partially permeable membrane

Osmotic pressure equation

\Pi = iMRT

What the variables in the osmotic pressure calculation (\Pi ) represent

\Pi is osmotic pressure, i is the van't Hoff factor, M is the solute molarity, T is the absolute temperature in kelvin, and R is the universal gas constant

Reverse osmosis

Reversal of osmosis; occurs when pressure greater than a solution's osmotic pressure is applied to a solution

Isotonic solution

Solution with the same concentration of solutes as the cell

Hypotonic solution

Solution with a lower concentration of solutes compared to the cell

Hemolysis

Rupture of red blood cells due to solvent entering cells from a less concentrated solution

Hypertonic solution

Solution with a higher concentration of solutes than the cell, causing water to move out of the cell

Crenation

Shriveling of red blood cells due to solvent leaving from a more concentrated solution

van't Hoff factor (i)

Defined as the ratio of solute particles in solution to the number of formula units dissolved