Exploring Mixtures and Their Separation

Vocabulary practice flashcards covering types of mixtures, concentration formulas, and various separation techniques based on the Class 9 Science notes.

Homogeneous mixtures (Solutions)

Mixtures having a uniform composition throughout their volume and showing no visible boundaries of separation.

Heterogeneous mixtures

Mixtures with non-uniform composition that consist of more than one phase and show visible boundaries of separation.

Solute

The substance which gets dissolved in a solution, such as sugar or salt.

Solvent

The substance in which dissolution takes place, such as water.

True solution

A mixture where solute particles are less than $10^{-9}m$ ($1\,nm$) in size, remain invisible to the naked eye, and do not scatter laser light.

Suspension

A heterogeneous mixture containing relatively large solid particles more than $1000\,nm$ in diameter that are visible to the naked eye and settle when undisturbed.

Colloid

A mixture containing particles between $1\,nm$ to $1000\,nm$ in size that are stable and scatter a beam of light.

Concentration of a solution

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

Oral Rehydration Solution (ORS)

A life-saving solution containing glucose, sodium chloride, potassium chloride, and sodium trinitrate in water, developed by Indian paediatrician Dr. Dilip Mahalanabis.

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

$\frac{\text{Mass of solute}}{\text{Mass of solution}} \times 100$; expresses grams of solute in $100\,g$ of total solution.

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

$\frac{\text{Mass of solute}}{\text{Volume of solution}} \times 100$; expresses grams of solute in $100\,mL$ of solution.

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

$\frac{\text{Volume of solute}}{\text{Volume of solution}} \times 100$; used for miscible liquids to express $mL$ of solute in $100\,mL$ of solution.

Solubility

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

Saturated solution

A solution that cannot dissolve any additional quantity of solute at its current particular temperature.

Solubility curves

Graphical representations showing how the solubility of different substances changes with temperature.

Crystallisation

A technique used to obtain pure solid crystals from a saturated solution by utilizing differences in solubility at different temperatures while cooling.

Crystal

A solid in which particles are arranged in a regular geometric pattern; examples include rock salt and snowflakes.

Distillation

A process to separate two miscible liquids with a boiling point difference of at least $25\,^\circ\text{C}$, involving heating to vaporize and then condensing to collect the distillate.

Fractional distillation

The process of separating components of a mixture with boiling point differences less than $25\,^\circ\text{C}$, commonly used in petroleum refineries.

Deg-Bhapka method

A traditional Indian distillation method used in Kannauj for extracting fragrances like Mitti ka Ittar from flowers.

Paper chromatography

A method of separating the components of a mixture, like coloured pigments in ink, based on different rates of movement in a solvent.

Separating funnel

A device used to separate two immiscible liquids based on their different densities.

Sublimation

The process by which a solid changes directly into a vapour state on heating without passing through the liquid state.

Deposition

The process where vapours condense directly back into a solid upon cooling without becoming a liquid.

Centrifugation

A method that separates components by spinning at high speed, causing heavier particles to move outwards due to centrifugal force.

Coagulation

The process of using a coagulant like alum (fitkari) to cause fine suspended impurities in a liquid to clump together into larger masses called floes.

Dispersed phase

The solute-like component or particles present in smaller quantity that remain distributed throughout a colloidal mixture.

Dispersion medium

The surrounding continuous medium in which the dispersed phase particles in a colloid are suspended.

Emulsions

A special type of colloid where both the dispersed phase and the dispersion medium are liquids, such as milk or butter.

Tyndall effect

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

Alloy

A homogeneous mixture of two or more metals, or a metal and a non-metal, such as brass or bronze, which cannot be separated by physical methods.

Brass

An alloy consisting of approximately $80\,\%$ copper and $20\,\%$ zinc.

Bronze

An alloy consisting of approximately $80\,\%$ copper and $20\,\%$ tin.