Solutions Vocabulary Review

Vocabulary flashcards covering the fundamental concepts of solutions, concentration units, laws of solubility, and colligative properties based on the Chapter 1 transcript.

Solution

A homogeneous mixture of two or more than two components where the composition and properties are uniform throughout the mixture.

Solvent

The component of a solution that is present in the largest quantity and determines the physical state in which the solution exists.

Solute

One or more components present in a solution in quantities other than the solvent.

Binary Solution

A solution consisting of exactly two components.

Mass Percentage ($w/w$)

The mass of a component in the solution divided by the total mass of the solution, multiplied by $100$.

Volume Percentage ($V/V$)

The volume of a component divided by the total volume of the solution, multiplied by $100$, commonly used for liquid-liquid solutions like a $35\% (v/v)$ solution of ethylene glycol.

Mass by Volume Percentage ($w/V$)

The mass of a solute dissolved in $100\,mL$ of the solution, a unit commonly used in medicine and pharmacy.

Parts Per Million (ppm)

A concentration unit used when a solute is present in trace quantities, defined as the number of parts of the component per $10^6$ total parts of the solution.

Mole Fraction ($x$)

The ratio of the number of moles of a specific component to the total number of moles of all the components in the mixture.

Molarity ($M$)

The number of moles of solute dissolved in one litre (or one cubic decimetre) of solution ($mol\,L^{-1}$).

Molality ($m$)

The number of moles of the solute per kilogram ($kg$) of the solvent ($mol\,kg^{-1}$).

Solubility

The maximum amount of a substance that can be dissolved in a specified amount of solvent at a specified temperature.

Dissolution

The process where a solid solute is added to a solvent and it dissolves, causing the concentration of the solute in the solution to increase.

Crystallisation

The process where solute particles in a solution collide with solid solute particles and separate out of the solution.

Saturated Solution

A solution in which no more solute can be dissolved at the same temperature and pressure, and which is in dynamic equilibrium with the undissolved solute.

Unsaturated Solution

A solution in which more solute can be dissolved at the same temperature.

Henry’s Law

States that at a constant temperature, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas present above the surface of the liquid ($p = K_H x$).

Bends

A painful and dangerous medical condition caused by the formation of nitrogen bubbles in the blood when scuba divers ascend quickly and pressure decreases.

Anoxia

A condition experienced by climbers at high altitudes where low blood oxygen causes weakness and inability to think clearly due to the lower partial pressure of oxygen.

Raoult’s Law

States that for a solution of volatile liquids, the partial vapour pressure of each component in the solution is directly proportional to its mole fraction ($p_1 = x_1 p_1^0$).

Ideal Solutions

Solutions that obey Raoult’s law over the entire range of concentration, characterized by $\Delta_{mix}H = 0$ and $\Delta_{mix}V = 0$.

Non-ideal Solutions

Solutions that do not obey Raoult’s law and show either positive or negative deviations from the predicted vapour pressure.

Azeotropes

Binary mixtures having the same composition in the liquid and vapour phase that boil at a constant temperature, making separation by fractional distillation impossible.

Colligative Properties

Properties of solutions that depend only on the number of solute particles relative to the total number of particles, regardless of their chemical identity.

Molal Elevation Constant (Ebullioscopic Constant)

Represented as $K_b$, it is the proportionality constant relating the elevation of boiling point to the molality of the solution ($\Delta T_b = K_b m$).

Molal Depression Constant (Cryoscopic Constant)

Represented as $K_f$, it is the proportionality constant relating the depression of freezing point to the molality of the solution ($\Delta T_f = K_f m$).

Semipermeable Membrane (SPM)

A membrane containing a network of submicroscopic holes that allows small solvent molecules to pass through while hindering larger solute molecules.

Osmosis

The process of the flow of solvent molecules through a semipermeable membrane from pure solvent to a solution, or from lower concentration to higher concentration.

Osmotic Pressure ($\Pi$)

The excess pressure that must be applied to a solution to prevent the passage of solvent molecules through a semipermeable membrane into the solution ($\Pi = C R T$).

Isotonic Solutions

Two solutions that have the same osmotic pressure at a given temperature, resulting in no osmosis across a semipermeable membrane.

Reverse Osmosis

The phenomenon where a pressure larger than the osmotic pressure is applied to the solution side, causing pure solvent to flow out of the solution through a membrane.

Abnormal Molar Mass

A molar mass value that is lower or higher than the expected value, due to the dissociation or association of solute particles in the solution.

van’t Hoff Factor ($i$)

A factor defined as the ratio of the normal molar mass to the abnormal molar mass, used to account for the extent of solute association or dissociation.