Exploring Mixtures and Their Separation

These flashcards cover the key concepts of mixture classification (homogeneous vs. heterogeneous), methods of separation (distillation, crystallization, chromatography, etc.), concentration calculations, and the properties of solutions, suspensions, and colloids.

Homogeneous mixture

A mixture that has a uniform composition throughout, such as sugar dissolved in water.

Heterogeneous mixture

A mixture that is not uniform and contains visible particles that settle over time, such as sand in water.

Solute

The substance in a solution that gets dissolved.

Solvent

The substance in a solution that dissolves the solute.

Solution

A homogeneous mixture formed when a solute is mixed with a solvent.

Concentration of a solution

The amount of solute dissolved in a given amount of solvent or solution.

Dilip Mahalanabis

An Indian paediatrician who developed the Oral Rehydration Solution ($ORS$) treatment for dehydration caused by diseases like diarrhoea.

Mass by mass percentage ($\% m/m$)

The concentration expressed as the number of grams of solute present in $100\,g$ of total solution.

Mass by volume percentage ($\% m/v$)

The concentration expressed as grams of solute present in $100\,mL$ of the solution, commonly used in medicines.

Volume by volume percentage ($\% v/v$)

The concentration expressed as millilitres of solute present in $100\,mL$ of the solution, often used for miscible liquids like perfumes.

Solubility

The maximum amount of solute that dissolves in a fixed quantity of solvent ($100\,mL$ or $100\,g$) at a given temperature.

Saturated solution

A solution that cannot dissolve any more solute at a specific temperature.

Solubility curve

A graph showing the relationship between solubility and temperature for specific solutes.

Crystal

A solid composed of particles arranged in a regular geometric pattern.

Crystallization

The laboratory process of forming crystals from a saturated solution to separate pure solids or purify substances.

Distillation

A method to separate miscible liquids by heating them until the liquid with the lower boiling point vaporises and then cooling the vapour back into liquid.

Deg-Bhapka method

A traditional distillation method used in Kannauj, India, to create natural perfumes like Mitti ka Ittar.

Fractional distillation

The process of separating components of a mixture with boiling point differences less than $25\,°C$, such as in petroleum refining.

Paper chromatography

A technique that separates components of a mixture based on their differing interactions and rates of movement through a solvent and paper.

Immiscible liquids

Liquids that do not mix and instead form separate layers, such as oil and water.

Separating funnel

An apparatus used to separate two immiscible liquids based on their different densities.

Sublimation

The process where a substance changes directly from the solid state to the vapour state without becoming a liquid.

Deposition

The process where vapours condense back into a solid without passing through the liquid state.

Alloy

A homogeneous mixture of two or more metals, or a metal and a non-metal, such as brass or bronze.

Suspension

A heterogeneous mixture in which solid particles larger than $1000\,nm$ do not dissolve and remain visible and suspended.

Centrifugation

The process of spinning a mixture at high speed so that centrifugal force causes heavier particles to move outward and settle at the bottom.

Paperfuge

A hand-powered, low-cost centrifugation tool used to detect diseases like malaria and anaemia in remote areas.

Coagulation

A process where a chemical substance causes fine suspended particles to clump together into larger masses.

Colloid

A mixture with particle sizes between $1\,nm$ and $1000\,nm$ that do not settle over time, such as blood or milk.

Tyndall effect

The scattering of light by particles in a colloid or suspension, making the path of the light beam visible.

Dispersed phase

The solute-like component or particles that are suspended in a colloid.

Dispersion medium

The component of a colloid in which the dispersed phase is suspended.

Emulsion

A type of colloid where both the dispersed phase and the dispersion medium are liquids.