Atoms

Atoms

• Elements
• Compounds
• Atoms
• 

What are atoms?

• Atoms are the building blocks of every single substance. They make up elements, compounds and mixtures. Atoms are made up of subatomic particles called protons, neutrons and electrons. Protons are positively charged, neutrons are neutral and electrons are negative.
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Atomic theory of matter

• The atomic theory of matter was developed by John Dalton in the 1800s.
• 1. Each element is composed of atoms2. All atoms of a given element are the same
• 3. Atoms can't be created or destroyed but
• can be rearranged to form different substances
• 4. Compounds are made up of more than one type of atom
• 

Elements

• Elements are the most basic material for
• building the world around you. Elements are entirely made from one type of atom. There are 118 elements. 92 are naturally made and 26 are man made. There are monatomic and molecular elements. There are only 6
• monatomic elements known in the world. Elements are put into a periodic table listed from lightest to heaviest.
• 

Classifying Elements

• Elements are classified into two groups, metallic and non-metallic.
• Metallic elements are:
• Ductile, malleable, shiny, good conductors, solid at room temperature (except mercury) Non-metallic elements are:
• Dull, brittle, not ductile, solid or gas at room temperature (except bromine)
• 

Compounds

• Compounds are two different types of elements put together. Compounds have properties that are usually very different from that of elements. Compounds can also form crystal lattices which are grid like structures. The atoms in a crystal lattice are very strongly bonded. Beach sand and table salt are two examples of compound lattices.
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Mixtures

• Mixtures are about physical propeties. Most of the things all around us are mixtures. Mixtures are more than 2 different types of elements put together or elements and compounds together. Mixtures don't have a chemical formula because it's not pure, it contains more than one chemical substance. Pure substances contain one chmeical substance.
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