More Lessons for IGCSE Chemistry
A series of free IGCSE Chemistry Activities and Experiments (Cambridge IGCSE Chemistry).
The Periodic Table
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.
Group 1 (alkali metals)
Group 1 elements are highly-reactive metals. They all have one electron in their outer energy level.
Group 0 (noble gases)
Group 0 elements are unreactive gases. They all have a full outer energy level, which is stable.
Atoms, Ions, Compounds
Structure of an atom
Matter is made from tiny building blocks called atoms.
Chemist use the Nuclear Model to describe atomic structure.
The sub-atomic particles are protons, electrons and neutrons.
An atom's mass is the mass of the nucleus (protons + neutrons).
The nucleus has a positive charge.
The overall charge of an atom is neutral.
Adding or removing electrons will give the atom a charge.
All materials are made of atoms. Some materials are elements and others are compounds.
There are about 118 materials that are made from one type of atom. These are called elements.
Molecules can be compounds or elements.
The number of protons identify the element.
Periodic Table of Elements
Metals, Non-metals, Transition metals
Transition metals form coloured compounds.
The group number indicates the number of electrons on the outer shell.
The period numbers indicates the number of shells.
History of the Periodic Table
Why did Mendeleev leave gaps in the periodic table?
1. What are atoms?
2. What is an ion?
3. What are compounds?
4. What are elements?
5. Describe how the periodic table is organised?
6. Why were there gaps in the early versions of the periodic table?.
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