Chemistry Igcse Gcse topics

Chemistry

Periodic table

The Periodic Table is a way of arranging what we know about the chemical elements

Each element in the Periodic Table is a different type of atom

The Periodic Table is arranged in atomic number order

Compounds are formed when two or more chemical elements react together.

An atom has a central nucleus. A nucleus contains one or more protons.

.The number of protons in the atomic nucleus gives the atomic number. 12.An atom contains one or more electrons. 13.The electrons are arranged in shells.

The elements are arranged in rows in the Periodic Table. 21.The rows of elements are called periods. 22.The higher the atomic number of an element, the higher the period. 23.The number of shells of electrons determines the period an element is in.

Physical properties of elements often change in a pattern down the group

States of matter

There are three different states of matter

Solid

Liquid

Gas

Arrangment

Close together

Far apart

Regular

Random

Movement of particles

Vibrate on the spot

Move around each other

Move quickly in all directions

Heat must be apllied to a substance for it to

A substance must be cooled for it to freeze or condense