Atoms

Inside an Atom The atom consists of three smaller particles. The positive charge neutron, negative charge electron and the neutron which has no charge. The protons and neutrons are packed together in the nucleus of the atom, which is the center of the atom. Electrons orbit around the nucleus in shells called electron shells. The most outer shells in atoms contain the most outer electrons. The most electron shells an atom can have is seven. This is explained by the Periodic Table.

Atom

Atom The nucleus in the atom is extremely small. If you had an atom the size of a football field, the nucleus in the center would be the size of a marble. Between the nucleus and the elctron shells exist empty space. This means just like on the football field, you would be able to pass through an atom.

Elements An element is a substance that cannot be broken down into any simpler substances by chemical or physical means. Examples include Gold, Silver, Copper, Helium, Oxygen, Carbon. All elements known to man are grouped together in the Periodic Table

Periodic Table It contains all known elements known to man. Hydrogen being the first element. You should know the first ten elements. The table is labelled by groups going across and columns called Periods going down. There are eight (8) groups and seven (7) Periods. Groups tell you how many electrons are in the most outer electron shell. For example, Sodium (Na), is in Group 1. Therefore it has one electron in the most outer shell. Ar is in Group 8, and so has eight electrons in the most outer shell. Periods tell you how many electron shells an element has.

How is the Periodic Table arranged? The Periodic Table is arranged by how many protons an element contains. Hydrogen which only has one proton is the first element in the table. The table is separated by the physical properties of the elements. Observe the table and state the changes in physical properties that change as you move to the right.

Compounds A compound consists of atoms of two or more different elements bounded together. They can be broken down into simpler substances by chemical means but not physically. The compound has properties that are different from it’s elements. Give examples of compounds.

Mixtures These consists of two or more different elements and/or compounds physically mixed together. They can be separated into its components by physical means, and  often retains many of the properties of its components.

Molecules These are a group of atoms bonded together. For example, water is a molecule. Water is known as H2O . If you look at your Periodic Table, you will see that H2Ois a combination of H (hydrogen) and (O) oxygen. Another molecule in everyday life is CO2 What combination of elements is that..and what do you call that molecule?