A: Metals are elements that usually exhibit lustre, are malleable and ductile, and conduct heat and electricity. Examples: iron and copper.

A: Non-metals are elements that are generally dull, brittle (if solid), and poor conductors of heat and electricity. Examples: sulfur and oxygen.

A: An alloy is a mixture of two or more elements, at least one of which is a metal, designed to improve properties. Example: steel (iron + carbon) is used in construction.

A: An ore is a naturally occurring rock that contains sufficient minerals for a metal to be extracted economically, such as bauxite for aluminium.

A: Native metals are metals found in nature in their free or native state, not combined with other elements. Example: native gold found in riverbeds.

A: Corrosion is the gradual destruction of metals by chemical reactions with their environment. Example: rusting of iron.

A: Malleability is the ability of a metal to be hammered or rolled into thin sheets without breaking, like aluminium foil.

A: Ductility is the ability of a metal to be drawn into thin wires, as seen in copper used for electrical wiring.

A: Lustre refers to the shiny appearance of a metal surface that reflects light, for example, a polished silver spoon.

A: Metals are used for cooking vessels because they conduct heat well, are strong, and can be shaped into desired forms.

A: Sonorous means producing a ringing sound when struck; many metals like iron and brass are sonorous and used in bells and musical instruments.

A: Not all metals are equally hard. Hardness varies—e.g., sodium is soft and can be cut with a knife, while iron is harder.

A: Iron, nickel and cobalt are common magnetic metals used in various applications.

A: Metals have free electrons that can move easily through the metal, enabling efficient conduction of electric current.

A: Aluminium is a light metal used in cooking utensils and aircraft parts because of its low density and strength.

A: Malleability is the ability to be flattened into sheets; ductility is the ability to be drawn into wires. Both are mechanical properties of metals.

A: Coins are made of metal because metals are durable, can be easily stamped with designs and resist wear.

A: The sonorous property is used to make musical instruments like cymbals and bells.

A: Non‑metals are generally poor conductors of heat and electricity, such as sulfur and phosphorus.

A: Carbon in the form of graphite is soft and leaves marks on paper, making it suitable for pencil leads.

A: Bromine is a non‑metal that is liquid at room temperature.

A: No, solid non‑metals are generally non‑sonorous and do not produce a ringing sound when struck.

A: Chlorine (a non‑metal) is used for water sterilisation because it kills bacteria and germs effectively.

A: Phosphorus is used in matches and fertilizers; white phosphorus is reactive and used carefully in industry.

A: Because non‑metals are poor conductors of electricity and cannot carry current efficiently.

A: Oxygen is essential for respiration in most living organisms.

A: Sulfur is used in the manufacture of sulfuric acid, which is important in several industries.

A: Magnesium burns with a bright white flame to form magnesium oxide (MgO), a white powder.

A: Sodium reacts vigorously with water producing sodium hydroxide and hydrogen gas, often with heat and flames.

A: Zinc reacts to form zinc chloride and hydrogen gas is liberated with bubbling (effervescence).

A: Copper is a less reactive metal and does not displace hydrogen from dilute acids under normal conditions.

A: 2Mg + O₂ → 2MgO (magnesium reacts with oxygen to form magnesium oxide).

A: Carbon burns in oxygen to form carbon dioxide, a colourless gas; sometimes it forms carbon monoxide under limited oxygen.

A: Reactive metals such as sodium and potassium react with air and moisture, so they are stored under oil to prevent contact and avoid reactions.

A: Sulfur + oxygen → sulfur dioxide (S + O₂ → SO₂), a gas with a pungent smell.

A: Because metals displace hydrogen from acids, forming a salt and releasing hydrogen gas (metal + acid → salt + H₂).

A: The reactivity series is a list of metals arranged according to their reactivity from highest to lowest, helping predict possible reactions.

A: Magnesium is more reactive than copper; magnesium reacts with oxygen vigorously, whereas copper does not react easily with oxygen or acids.

A: Iron is more reactive than silver and can displace silver from its salt solution; comparing with zinc, iron is less reactive than zinc so it will not displace zinc from zinc salts.

A: Sodium is more reactive because it loses electrons more readily and reacts more vigorously with water and air than copper.

A: Iron rusts and needs protection, while gold does not rust; this shows that gold is much less reactive than iron.

A: Metals low in the reactivity series (like gold) are often found native and need simple extraction, while very reactive metals require complex extraction methods.\div>

A: Rusting requires the presence of iron, oxygen and water (moisture); electrolytes like salt speed up the process.

A: Iron + oxygen + water → hydrated iron(III) oxide (rust).

A: Painting provides a protective coating that prevents air and water from reaching the iron surface, thus preventing rusting.

A: Galvanisation is the process of coating iron or steel with zinc; zinc protects iron by corroding preferentially (sacrificial protection).

A: Alloying can produce metals like stainless steel (iron + chromium) that resist rust and corrosion better than pure iron.

A: Brass (copper + zinc) is hard and malleable; it is used in musical instruments, fittings and decorative items.

A: Stainless steel resists corrosion due to chromium content, is durable, and easy to clean, making it ideal for kitchen sinks.

A: Aluminium is used for cooking utensils due to good thermal conductivity and for aircraft parts due to its light weight and strength.