Course

O Level Chemistry: Metals, Environment and Industry (5070)

Name: O Level Chemistry: Metals, Environment and Industry (5070)
Price: 999 BDT

5070 topics 9 and 10 taught step by step: properties and uses of metals, alloys, the reactivity series, rusting, extraction of iron and aluminium, water, fertilisers, air quality and climate.

64 lessons10h 33mEnglish

What you'll learn

Compare metals with non-metals and link each use of aluminium, copper and stainless steel to the property it needs
Explain from a structure diagram why an alloy is harder than a pure metal
Recall the reactivity series, use it to predict reactions with water, steam, acid and metal ions, and deduce an order from results
State the conditions for rusting and explain barrier methods, sacrificial protection and galvanising
Write an equation for every step of the blast furnace and the half-equations for extracting aluminium
Test water, describe water treatment, and name each air pollutant with its source, its effect and a way to reduce it

Requirements

Atoms, ions, bonding, formulae and the mole, as taught in Matter, Bonding and the Mole
Redox and electrolysis at O Level, as taught in Reactions and the Periodic Table, helps with chapters 3 and 4
A periodic table and a calculator beside you

Course content

64 lessons · 10h 33m

9.1-9.3 · Properties of metals, uses and alloys

Compare metals with non-metals, see how metals react with oxygen, water and acids, match each use to a property, and explain why an alloy is harder than a pure metal.

0/9

Physical properties of metals and non-metals

Metals conduct, bend and melt high; most non-metals do not. Sort the scrap box by what each material does.

Preview11m 2.

Metals reacting with oxygen

A metal burns to a metal oxide, and the mass goes up because oxygen joins it.

Preview11m

Metals reacting with water and dilute acids

Three general equations: water gives a hydroxide, steam an oxide, an acid a salt. All three give hydrogen.

12m

Uses of metals

Aluminium flies, carries power and wraps food; copper wires the house. Each use needs one property.

11m

Alloys

An alloy is a metal mixed with other elements: brass, stainless steel, and why spoons are not pure iron.

11m

Why alloys are harder than pure metals

Different sized atoms stop the layers sliding. Spot the alloy in a structure diagram.

12m

Metals and alloys: practice

A timed drill of mixed cards, then mixed questions with full working.

Metals and alloys: exam practice

Exam-style questions with marks, mark schemes and full worked solutions.

15m

Metals and alloys: summary

The key points, equations and common mistakes on one screen, with cards to revise from.

9.4 · Reactivity series

Learn the reactivity series, explain it as the tendency to form positive ions, use it to predict reactions with water, steam, acid and metal ions, and deduce an order from results.

0/10

The reactivity series

Twelve places from potassium to gold, with carbon and hydrogen as markers. Higher means it loses electrons more easily.

Preview11m 2.

Reactions of potassium, sodium and calcium with cold water

Potassium bursts into flame, sodium whizzes, calcium fizzes. All three make a hydroxide and hydrogen.

Preview11m

Reaction of magnesium with steam

Magnesium barely reacts with cold water but burns in steam to give magnesium oxide and hydrogen.

11m

Reactions of metals with dilute hydrochloric acid

Magnesium fizzes fast, zinc steadily, iron slowly; copper, silver and gold sit below hydrogen and do nothing.

11m

Displacement reactions

A more reactive metal pushes a less reactive metal out of its compound. An iron nail turns copper-coloured.

12m

The apparent unreactivity of aluminium

Aluminium is high in the series, yet pans last for years. A thin oxide layer keeps water and acid away.

10m

Deducing an order of reactivity from results

Use a displacement grid, temperature rises or bubbling to put unknown metals in order.

12m

Reactivity series: practice

A timed drill of mixed cards, then mixed questions with full working.

Reactivity series: exam practice

Exam-style questions with marks, mark schemes and full worked solutions.

15m

10.

Reactivity series: summary

The key points, equations and common mistakes on one screen, with cards to revise from.

9.5 · Corrosion of metals

State what iron needs to rust, then explain the three ways to stop it: a barrier, a sacrificial metal, and galvanising, which does both.

0/7

Conditions for rusting

Iron rusts only when water and oxygen are both present. Three test tubes prove it.

Preview11m 2.

Barrier methods

Paint, grease and plastic keep water or oxygen away from the iron, but only while the barrier is unbroken.

Preview11m

Sacrificial protection

A more reactive metal loses electrons first, so it corrodes and the iron does not.

11m

Galvanising

A zinc coat is a barrier and a sacrificial metal at once, so a scratched roof still does not rust.

11m

Corrosion of metals: practice

A timed drill of mixed cards, then mixed questions with full working.

Corrosion of metals: exam practice

Exam-style questions with marks, mark schemes and full worked solutions.

15m

Corrosion of metals: summary

The key points, equations and common mistakes on one screen, with cards to revise from.

9.6 · Extraction of metals

Link the extraction method to the reactivity series, follow iron through the blast furnace with an equation for every step, and explain how aluminium is extracted by electrolysis.

0/9

Metal ores and the reactivity series

Gold is found as metal, iron is heated with carbon, aluminium needs electricity. The series tells you which.

Preview11m 2.

The blast furnace: burning coke

Coke burns to give heat and carbon dioxide, which more coke turns into carbon monoxide.

Preview11m

The blast furnace: reducing iron(III) oxide

Carbon monoxide takes the oxygen from iron(III) oxide, leaving molten iron.

12m

The blast furnace: limestone and slag

Limestone breaks down to calcium oxide, which removes sand as slag.

12m

Extraction of aluminium: cryolite and carbon anodes

Aluminium is above carbon, so it is won by electrolysis. Cryolite saves energy; the anodes burn away.

12m

Extraction of aluminium: the electrode reactions

Aluminium ions gain electrons at the cathode; oxide ions lose them at the anode.

12m

Extraction of metals: practice

A timed drill of mixed cards, then mixed questions with full working.

Extraction of metals: exam practice

Exam-style questions with marks, mark schemes and full worked solutions.

15m

Extraction of metals: summary

The key points, equations and common mistakes on one screen, with cards to revise from.

10.1-10.2 · Water and fertilisers

Test for water and for pure water, say what natural water contains and which substances help or harm, follow water treatment, and explain what NPK fertilisers supply.

0/12

Chemical tests for water

Anhydrous copper(II) sulfate turns blue and anhydrous cobalt(II) chloride turns pink when water is present.

Preview11m 2.

Testing the purity of water

Pure water melts at exactly 0 °C and boils at exactly 100 °C. Impurities shift both.

Preview11m

Why distilled water is used in practical chemistry

Tap water carries dissolved ions that can give a false test result. Distilled water has far fewer.

10m

Substances in natural water

River water carries oxygen, minerals, plastics, sewage, microbes, nitrates and phosphates. Some of these help life.

11m

Harmful substances in water

Toxic metals, plastics, sewage microbes, and nitrates and phosphates that use up the oxygen.

11m

Treatment of the domestic water supply

Settle, filter, carbon, chlorine: each step removes one kind of problem.

11m

Ammonium salts and nitrates as fertilisers

Plants need nitrogen. Ammonium salts and nitrates supply it, and ammonia plus an acid makes them.

11m

NPK fertilisers

Nitrogen, phosphorus and potassium, in the ratio on the bag. Read a 20-10-10 label.

11m

The percentage of nitrogen in a fertiliser

Work out the nitrogen share of a fertiliser from its formula, then choose the best buy.

12m

10.

Water and fertilisers: practice

A timed drill of mixed cards, then mixed questions with full working.

11.

Water and fertilisers: exam practice

Exam-style questions with marks, mark schemes and full worked solutions.

15m

12.

Water and fertilisers: summary

The key points, equations and common mistakes on one screen, with cards to revise from.

10.3 · Air quality and climate

State what clean air contains, name each pollutant with its source and effect, explain global warming and acid rain and how to reduce them, and write the photosynthesis equation.

0/11

The composition of clean air

Clean dry air is about 78% nitrogen and 21% oxygen; the last 1% is noble gases and carbon dioxide.

Preview11m 2.

Sources of air pollutants

Burning fuel with plenty of air gives carbon dioxide; with too little it gives carbon monoxide and soot.

Preview11m

Effects of air pollutants

Carbon monoxide is toxic, particulates harm the lungs, and oxides of sulfur and nitrogen make acid rain.

11m

Greenhouse gases and global warming

Carbon dioxide and methane absorb the heat the Earth gives off and send some back down.

11m

Reducing climate change

Plant trees, farm fewer animals, burn less fossil fuel, use hydrogen, wind and sunlight. Say why each helps.

11m

Acid rain and how to reduce it

Sulfur dioxide and nitrogen oxides make rain acidic. Low-sulfur fuel and calcium oxide scrubbers cut them.

11m

Oxides of nitrogen and catalytic converters

The hot engine joins nitrogen and oxygen; the converter turns NO and CO back into N2 and CO2.

11m

Photosynthesis

Plants use light and chlorophyll to turn carbon dioxide and water into glucose and oxygen.

11m

Air quality and climate: practice

A timed drill of mixed cards, then mixed questions with full working.

10.

Air quality and climate: exam practice

Exam-style questions with marks, mark schemes and full worked solutions.

15m

11.

Air quality and climate: summary

The key points, equations and common mistakes on one screen, with cards to revise from.

About the creator

8bitlesson

Cambridge O Level, A Level and university courses, taught through interactive labs.

Mentora builds the sciences and mathematics as things you can move rather than videos you watch. Cambridge O Level and A Level mathematics, physics, chemistry and accounting, a primary mathematics track, and first-year university computer science. Every lesson works a real exam question end to end.