More Lessons for IGCSE Chemistry
A series of free IGCSE Chemistry Lessons (Cambridge IGCSE Chemistry).
The Periodic Table, Trends in groups, Trends across a period, Chemical bonding in elements and compounds, Chemical formulas of elements and compounds, Metals, alloys and crystals.
The following periodic table highlights the diatomic elements: hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine and astatine
To help you remember: the diatomic elements form a seven starting from nitrogen (element number 7).
Another way to remember: the diatomic elements names end with "gen" or "ine".
The following table shows the valency for some simple positive and negative ions and polyatomic ions. Scroll down the page for examples and solutions.
The Periodic Table
The elements in the same group of the Periodic table have the same number of outer electrons. This means that they react in the same way.
Explain why elements in group 0 do not react.
Group 0 elements are unreactive gases. They all have a full outer-energy level, which is stable.
Physical Properties of Metals and Non Metals
Chemistry of Groups 1, 7 and 0
Properties of Group 1: The Alkali Metals,
Group 7: The Halogens,
Group 0: The Noble Gases
Trends in the Properties of Elements of Period 3
Transition elements (metals)
Explore the properties of transition elements and also their reactivity (in comparison to alkali metals).
How ionic, covalent and metallic bonds are formed?
How to draw dot-and-cross diagrams to represent bonding?
Properties of Ionic Compounds
Giant ionic lattices and how these determine two key properties of ionic compounds
Properties of simple covalent molecules
Properties of Giant Covalent Molecules
Formula of Ionic Compounds
How to determine the formula of an ionic compound given the charges on the ions?
Crossover method of writing formulas for ionic compounds
Structure of substances
How the properties of substances are related to the their structure and the kind of bonding they have?
Giant ionic structures, simple molecules, giant covalent structure, giant metallic structure.
Metals and Alloys
Properties of metals and of alloys and how they relate to the structures.
Examples and properties of Alloys
Stainless steel and Brass
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