Metals and Non-metals

Vocabulary practice flashcards covering physical and chemical properties of metals and non-metals, extraction of metals, corrosion, alloys, and experimental setups from Chapter 3.

Metallic Lustre

The property of metals in their pure state having a shining, light-reflecting surface.

Malleability

The physical property of metals that allows them to be beaten into thin sheets; gold and silver are the most malleable metals.

Ductility

The ability of a metal to be drawn into thin wires. Gold is the most ductile metal, allowing a wire of about $2\,\text{km}$ length to be drawn from one gram of gold.

Thermal Conductivity in Metals (Experimental Setup)

An experimental demonstration showing that metals conduct heat toward a free end, causing wax holding a pin to melt while the metal wire itself does not melt.

Sonorous

The characteristic property of metals that cause them to produce a ringing sound when struck against a hard surface.

Allotrope

Different physical forms of the same element; for example, carbon exists as diamond (the hardest natural substance known) and graphite (an electrical conductor).

Amphoteric Oxides

Metal oxides that react with both acids as well as bases to produce salts and water, such as aluminium oxide ($Al_2O_3$) and zinc oxide ($ZnO$).

Anodising

A process of forming a thick, corrosion-resistant aluminium oxide protective layer by electrolysing a clean aluminium article as the anode in dilute sulphuric acid.

Apparatus for Action of Steam on a Metal

A laboratory assembly where water-soaked glass wool is heated to generate steam that passes over a heated metal sample, releasing hydrogen gas collected over water.

Aqua Regia

A freshly prepared, highly corrosive and fuming mixture of concentrated hydrochloric acid ($HCl$) and concentrated nitric acid ($HNO_3$) in a $3:1$ volume ratio capable of dissolving gold and platinum.

Displacement Reaction of Metals

A chemical reaction in which a more reactive metal displaces a less reactive metal from its aqueous salt solution or molten compound.

Reactivity Series (Activity Series)

A vertical arrangement of metals in the order of their decreasing chemical reactivities, placing potassium ($K$) at the top and gold ($Au$) at the bottom.

Ionic Compounds (Electrovalent Compounds)

Compounds formed by the electrostatic attraction between oppositely charged ions created by the transfer of valence electrons from a metal to a non-metal.

Mineral

Naturally occurring inorganic elements or compounds found in the earth's crust.

Ore

A naturally occurring mineral containing a high percentage of a particular metal from which that metal can be profitably and conveniently extracted.

Gangue

The undesirable, commercially worthless earthy and rocky impurities (such as sand and soil) that contaminate mined mineral ores.

Roasting

The metallurgical process of converting sulphide ores into metal oxides by heating them strongly below their melting point in the presence of excess air.

Calcination

The metallurgical process of converting carbonate ores into metal oxides by heating them strongly in limited air or in the absence of air.

Thermit Reaction

A highly exothermic reduction reaction between iron(III) oxide ($Fe_2O_3$) and aluminium powder ($Al$) that produces molten iron used to weld railway tracks and repair cracked machine parts.

Electrolytic Refining

A purification technique where an impure metal serves as the anode, a pure metal strip acts as the cathode, and a metal salt solution acts as the electrolyte to deposit pure metal at the cathode.

Anode Mud

The insoluble impurities that drop and collect at the bottom beneath the anode during the electrolytic refining of metals.

Corrosion Experiment (Rusting Conditions)

A laboratory investigation showing that iron nails rust only in the presence of both oxygen and water (test tube A), but not in boiled water covered with oil (test tube B) or dry air with anhydrous calcium chloride (test tube C).

Galvanisation

A protective method used to prevent iron and steel from rusting by applying a thin surface coating of zinc metal.

Alloy

A homogeneous mixture of two or more metals, or a metal and a non-metal, prepared by melting the primary metal and dissolving other elements in definite proportions.

Amalgam

An alloy formed when mercury ($Hg$) is mixed with one or more other metals.

Solder

A low-melting-point alloy composed of lead ($Pb$) and tin ($Sn$) used primarily for welding and joining electrical components.

Iron Pillar at Delhi

An ancient Indian metallurgical marvel near Qutub Minar built more than $1600\,\text{years}$ ago; standing $8\,\text{m}$ tall and weighing $6\,\text{tonnes}$ ($6000\,\text{kg}$), renowned for its extraordinary resistance to rust.