Elements and Atoms

Atoms

• Every substance in the universe is made up of atoms. There are only around a hundred types of atoms but they can be arranged in different combinations to create countless tyoes of different substances
• Atoms are round like tiny balls. They are so small that they cannot be seen by any optical microscope. Instead scientists must use STM's (Scanning Tunnelng Microscope)
• https://www.youtube.com/watch?v=R1RMV5qhwyE (Embed)

Elements

• Elements are substances that are made up of one type of atom.
• Elements can be grouped into 2 main categories:
• Metallic and Non- metallic
• There are 118 known elements. 92 occur naturally but the rest are synthetic and must be made in a laboratory
• Scientistst display all the known elements on the periodic table.
• The periodic table lists the elements from heaviest to lightest.
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Periodic Table

Metallic and Non-Metallic elements

• Metallic
• Tend to be shiny
• Solid at room temperature besides mercury
• Good conductors of heat and electricity
• Can be bent and hammered into sheets
• Can be stretched into wires
• Non-mettalic
• Tend to be dull
• Do not conduct heat or electricity
• Break or crumble when you bend them
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• Caption: Mettalic Elements

How Elements are made up

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• 
• Caption: Atoms can be arranged in a cluster of atoms called moleculesThis is an oxygen molecule. Oxygen molecules are always made up of 2 atoms. This is why oxygen also known as O2
• Caption: Atoms can also be arranged in large grid like structures called Lattices

Compounds

• Most things we see in day to day life are compounds. This means that they are made up of more than one element.
• Compounds can also be made of molecules and lattices.
• Like elements every compound has its unique set of charecteristics called properties. The propertys of compounds are different to the elements that make them up.
• Molecular compound names contain their element synbol and how much atoms of each were in it. For example: A glucose molecule has 6 carbon atoms, 12 Hydrogen atoms and 6 oxygen atoms. Its symbol isC12 H12 O6
• Mixtures are substances that are made up of elements and compounds.
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• Caption: This is a water molecule. Its formula is H2O meaning it contains 2 Hydrogen atoms and 1 oxygen atom.

John Daltons Theory

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• Caption: John Daltons Atomic Theory of Matter
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• Caption: John Dalton is considered to be the first person to propose the fundamental ideas behind the modern atomic theory of matter

Inside Atoms

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• Atoms are made up of very small particles called subatomic particles.
• These particles are electrons, protons and neutrons.
• The protons and neutrons are in a clump at the centre of the atom and the neutrons orbit them in different layers or shells.This is how they form an electron cloud.
• layer 1 = 2 electrons
• layer 2 = 8 electrons
• layer 3 = 18 electrons
• layer 3 = 32 electrons
• Most of an atom is empty space. If the nucleus was the size of a golf ball then the electron cloud would be the size of a football stadium and the electrons would be the size of a grain of sand.
• The positive charge on protons mean they would normally repel each other but the neutrons and protons in the nucleus are held together by the strong force. This is a force 100,000,000,000,000,000,000,000,000,000,000,000,000 times stronger then gravity
• Caption: Inside an atom

Other Resources

• Elements
• Compounds
• A closer look at atoms
• Elements
• These are other resources that you can use that are on the same topic and might help you out