Welcome to the official Metals Non Metals - AHC RO/ARO Study Guide study resource on SJMaths, specially curated for Allahabad High Court RO/ARO Mains candidates and aspirants. This page features high-yielding study material, core concepts, essential formulas, shortcut strategies, and topic-wise revision notes structured to maximize your exam performance.
Key Features & Learning Modules:
Step-by-Step Problem Solving: Clear conceptual breakdowns and model solutions for foundational to advanced level questions.Formulas & Shortcut Rules: Instant access to important mathematical formulas, identities, theorems, and time-saving calculation tricks.Interactive Practice & Revision: High-probability exam questions designed to strengthen problem-solving speed and accuracy.
Tip: Bookmark this page for daily revision and practice tests. Use SJMaths' interactive modules to track your preparation progress.
Click on any milestone card below to view standardizing achievements and timeline parameters.
Metals & Non-metals
Master physical and chemical properties of metals and non-metals, the reactivity series parameters, metallurgy processes (enrichment, calcination, roasting, refining), alloys, corrosion prevention, and important industrial applications.
1. Properties of Metals vs Non-metals & The Reactivity Series
Physical Properties: Metals are generally malleable, ductile, lustrous, sonorous, and good conductors of heat and electricity. Non-metals are usually brittle, non-lustrous (except Iodine), and poor conductors (except Graphite).Chemical Properties:
Metal + Oxygen → Metal Oxide (generally basic, e.g., Na₂O, MgO). Amphoteric oxides (Al₂O₃, ZnO) react with both acids and bases.
Metal + Water → Metal Oxide/Hydroxide + Hydrogen gas . Sodium reacts violently with cold water; Magnesium reacts only with hot water; Aluminum, Iron, and Zinc react only with steam; Gold and Silver do not react at all.
Metal + Acid → Salt + Hydrogen gas . Copper does not react with dilute HCl. Metals do not evolve H₂ gas with nitric acid (HNO₃) because HNO₃ is a strong oxidizing agent that oxidizes H₂ to H₂O (except Mg and Mn, which react with very dilute HNO₃).
Physical & Chemical Comparison:
Property
Metals
Non-metals
State at RT
Solid (except Mercury which is liquid)
Solids, Gases (except Bromine which is liquid)
Oxides
Basic or Amphoteric (e.g., Na₂O, Al₂O₃)
Acidic or Neutral (e.g., SO₂, CO, H₂O)
Electrochemical
Electropositive (lose electrons to form cations)
Electronegative (gain electrons to form anions)
Reducing / Oxidizing
Act as Reducing agents
Act as Oxidizing agents
2. Occurrence of Metals, Important Ores, and Metallurgy Steps
Definitions:
Minerals: Naturally occurring inorganic substances containing metals found in the Earth's crust.
Ores: Minerals from which metals can be extracted profitably and conveniently. All ores are minerals, but not all minerals are ores.
Gangue: Unwanted impurities like soil, sand, and rocky materials present in the mined ore.
Important Ores (Highly Tested in Exams):
Metal
Ore Name
Chemical Composition
Type
Aluminum
Bauxite
Al₂O₃·2H₂O
Oxide
Iron
Hematite / Magnetite
Fe₂O₃ / Fe₃O₄
Oxide
Copper
Copper Pyrites / Copper Glanze
CuFeS₂ / Cu₂S
Sulfide
Mercury
Cinnabar
HgS
Sulfide
Zinc
Zinc Blende / Calamine
ZnS / ZnCO₃
Sulfide / Carbonate
Lead
Galena
PbS
Sulfide
Calcium
Gypsum / Limestone
CaSO₄·2H₂O / CaCO₃
Sulfate / Carbonate
Metallurgical Processes:
Concentration / Enrichment: Removing gangue using hydraulic washing, magnetic separation, froth floatation (for sulfide ores), or chemical leaching.
Conversion to Oxide: Carbonate ores undergo Calcination , while Sulfide ores undergo Roasting . Oxides are easier to reduce than carbonates/sulfides.
Parameter
Calcination (निस्तापन)
Roasting (भर्जन)
Ore Type
Used for Carbonate/Hydrated Ores
Used for Sulfide Ores
Air Supply
Heated in the absence or limited supply of air
Heated in the presence of excess air
By-product Gas
Carbon dioxide (CO₂) is released
Sulfur dioxide (SO₂) is released
Example Reaction
ZnCO₃ → ZnO + CO₂
2ZnS + 3O₂ → 2ZnO + 2SO₂
Reduction of Metal Oxides: Carbon (C) reduction is used for zinc, iron, and lead. Highly reactive metals like Na, Ca, Al are used as reducing agents for oxides of Mn or Cr (Thermite Reaction: Fe₂O₃ + 2Al → 2Fe + Al₂O₃ + Heat). Metals at the top of the series (Na, Mg, Ca) must be reduced via electrolysis of their molten chlorides (e.g., Down's Process for Sodium).
3. Alloys, Amalgams, Corrosion, and Prevention Methods
Alloys: Homogeneous mixtures of two or more metals, or a metal and a non-metal. Alloying improves mechanical properties, electrical resistance, and corrosion resistance.
Amalgam: An alloy in which one of the metals is Mercury (e.g., sodium amalgam, dental amalgam).
Important Alloys & Compositions (Highly Tested in Exams):
Alloy Name
Composition (Constituents)
Key Properties & Industrial Uses
Brass (पीतल) Copper (Cu: 60-80%) + Zinc (Zn: 20-40%)
Malleable, corrosion-resistant; used in utensils, musical instruments, decorative items.
Bronze (कांसा) Copper (Cu: 88%) + Tin (Sn: 12%)
Very strong, resistant to corrosion; used in statues, medals, bells, coins.
Solder (टांका) Lead (Pb: 50%) + Tin (Sn: 50%)
Low melting point; used extensively for joining electrical wires.
Stainless Steel Iron (Fe) + Carbon (C: 0.1-1.5%) + Chromium (Cr: 18%) + Nickel (Ni: 8%)
Hard, does not rust or stain; used in cutlery, surgical instruments, kitchenware.
Duralumin Aluminum (Al: 95%) + Copper (Cu: 4%) + Magnesium (Mg: 0.5%) + Manganese (Mn: 0.5%)
Lightweight and strong as steel; used in aircraft bodies and space vehicles.
German Silver Copper (Cu: 50%) + Zinc (Zn: 30%) + Nickel (Ni: 20%) Note: Contains 0% Silver!
Silver-like appearance; used in tableware, jewelry, decorative pieces.
Alnico Aluminum (Al) + Nickel (Ni) + Cobalt (Co) + Iron (Fe)
Highly magnetic; used to manufacture powerful permanent magnets.
Corrosion of Metals:
Iron (Rusting): Formed when iron reacts with oxygen and water to form Hydrated Ferric Oxide (Fe₂O₃·xH₂O), a reddish-brown flaky substance.
Copper: Reacts with moist carbon dioxide in the air to slowly form a basic copper carbonate green coating: CuCO₃·Cu(OH)₂.
Silver: Reacts with hydrogen sulfide (H₂S) gas in air to form a black coating of Silver Sulfide (Ag₂S).
Prevention Methods:
Painting / Greasing: Forms a barrier excluding moisture and air.
Galvanization: Coating iron or steel with a thin protective layer of Zinc . Zinc acts as a sacrificial anode because it is more reactive than iron and oxidizes preferentially.
Anodizing: Creating a thick oxide layer on aluminum (via electrolysis) to prevent further oxidation.
Chrome Plating: Electroplating chromium onto steel to provide resistance to corrosion and a shiny finish.
Historical Milestones in Metallurgy & Material Science
c. 5000 BCE — The Chalcolithic (Copper) Age : First extraction of metals from ores. Copper is smelted and utilized for tools, ending reliance on pure stone.c. 3300 BCE — The Bronze Age : Discovery of alloying. Combining copper with tin produces bronze, a much harder and more durable material.c. 1200 BCE — The Iron Age : Development of high-temperature smelting techniques allowed extraction of iron, revolutionizing agriculture and weaponry.1825 — Isolation of Aluminum : Hans Christian Ørsted isolates impure aluminum. Later, Friedrich Wöhler isolates pure aluminum powder in 1827.1886 - 1888 — Hall-Héroult & Bayer Processes : Charles Martin Hall and Paul Héroult independently develop electrolytic aluminum extraction. Karl Joseph Bayer extracts pure alumina from bauxite, making aluminum a mass industrial metal.
Key Questions & Answers
Which metal is liquid at room temperature, and which non-metal is liquid at room temperature? The metal is Mercury (Hg), and the non-metal is Bromine (Br). Both exhibit low melting points due to their specific electronic and atomic structures.
What is an amphoteric oxide? Provide two key examples. An amphoteric oxide is a metal oxide that reacts with both acids and bases to produce salt and water (showing both acidic and basic properties). Examples: Aluminum oxide (Al₂O₃) and Zinc oxide (ZnO).
Why are Sodium and Potassium metals stored under kerosene oil? They are highly reactive metals at the top of the reactivity series. They react vigorously with air (oxygen) and water (moisture) at room temperature, catching fire. Storing them under kerosene prevents contact with oxygen and moisture.
What is the difference between Calcination and Roasting? • Calcination : Heating carbonate ores strongly in the absence or limited supply of air to expel carbon dioxide. • Roasting : Heating sulfide ores strongly in the presence of excess air to convert them into oxides and release sulfur dioxide.
Memory Aids
Mnemonic 1: The Reactivity Series : Remember metals in decreasing order of reactivity: • P lease → P otassium (K) • S top → S odium (Na) • C alling → C alcium (Ca) • M e → M agnesium (Mg) • A → A luminum (Al) • Z ebra → Z inc (Zn) • I → I ron (Fe) • T ry → T in (Sn) • L earning → L ead (Pb) • H ow → H ydrogen (H) • C opper → C opper (Cu) • S aves → S ilver (Ag) • G old → G old (Au)Mnemonic 2: Brass vs Bronze Compositions : Avoid confusion between these copper alloys: • Bra ss contains Copper (Cu) + Z inc (Zn). (Think of the "s" sound pointing to the "z" in zinc). • Bro nz e contains Copper (Cu) + Ti n (Sn).
Common Exam Traps
Trap 1: Thinking all metals are hard. Group 1 alkali metals like Sodium (Na), Potassium (K), and Lithium (Li) are so soft they can easily be cut with a kitchen knife.
Trap 2: Assuming non-metals never conduct electricity. Graphite , an allotrope of carbon, has free valence electrons moving between carbon layers, making it an excellent electrical conductor.
Trap 3: Confusing the cathode and anode charges in electrolytic refining. The anode is positive and consists of the impure metal. The cathode is negative and consists of a thin strip of pure metal. Positively charged metal ions migrate to the cathode to get reduced.
Trap 4: Assuming iron rusts solely in the presence of water. Rusting of iron requires both oxygen and moisture (water) . Iron placed in boiled distilled water covered with oil (excluding air) or in dry air with silica gel (excluding moisture) will not rust.
Next: Practice Zone
Click on the options to check your answer instantly. Click "Show Explanation" to read step-by-step
solutions.
Next: Mock Test
0/15
Test
Completed!
Restart Test