Atomic structure and Electron arrangement

Atomic structure and Electron arrangement

1. Particles

   • Atom
     • Smallest particle of an element
     • Can be split up
   • Molecule
     • Non metal atoms chemically bonded together
     • Specific formula
   • Element
     • Only one type of atom in it
     • Molecules of elements e.g. oxygen, diatomic
     • pure substance
   • Compound
     • Pure substance
     • More than one type of element chemically bonded together
     • Represented by chemical formula
   • Mixture
     • Usually separated by physical techniques
       • Filtering and distillation
     • Impure substance
     • made from different Elements and Compounds

2. Electron shells

   • First shell - 2
   • Second shell-8
   • Third shell-8
   • when shell 4 has 2 electrons in it, 3 can take up to 18
   • When shell 5 has 2 in it, 4 can have up to 18, when shell six has 2 in it, 4 can have up to 32
     • It goes on like this.
   • can lose or gain electrons
     • if loses, becomes positively charged
     • if gains, becomes negatively charged

3. isotopes

   • can be Radioactive or non radioactive
   • Same amount of protons and electrons but different number of neutrons
     • same atomic number different mass number

4. Moles

   • Mass = MR*moles
   • Avagadro constant = 6.02*10 to the 23
   • Volumes of gasses
     • Volume of gas at room temp/ pressure= number of moles *24