Year 11 science

Year 11 science

1. Atoms have a small nucleus Surrounded by Electrons

   • 1)Nucleus middle atom. 2)Tiny compared rest atom. 3)Contains protons + neutrons. 4)Protons positively charged. 5)Neutrons no charge.
   • 1)Electrons around the nucleus. 2)Negatively charged. 3)Move shells around nucleus

2. Know your Particles

   • 1)Proton= mass of 1 and charge of +1 2) Neutron-mas of 1 and charge of 0 3) Electron= mass of 1/2000 and charge of -1

3. Number of protons equals number of electrons

   • 1) Atoms no charge 2) Charge elcetrons same protons but opposite 3) Number of protons equals number of electrons atom

4. Electron Shell Rules

   • Always move shells
   • Inner shells always filled first
   • Certain number of electrons: 1st shell=2 2nd shell=8 3rd shell=8
   • Atoms happier full electron shells
   • Most atoms outer shell not full want to react

5. Follow the rules to work out electronuc configurations

   • 1)Nitrogen seven protons seven electrons 2) Look Electron shell rules first shell only take 2 electrons second maxinum 8 electrons 3) Electronic configuration nitrogen 2,5.

6. Elements contain one type of atom only

   • Elements: Copper, Aluminium, Iron, Oxygen, Nitrogen.

7. Each element has an atomic number and a mass number

   • 1) Atomic number protons in an atom 2)Atom number elements different 3) Each element has a certain number protons 4) Number prtons atom decides element 5) Elemnet helium 2 protons any atom 2 protons helium 6) Mass number protons and neutrons in atom

8. Relative atomic mass is an average

   • 1) Sometimes different forms same element2) Same number protons 3) Each element certain number protons 4) All different mass numbers work out average mass 5) Average mass different forms element relative atomic mass

9. Mendeleev put the elemnts in groups

   • 1) 1869 Mendeleev put elements he knew table 2) Did based on properties compounds 3) Table placed elements similar properties vertical gropus 4) Found left gaps table

10. Mendeleev used his table to predict new elemts

    • 1) Gaps elements clever 2) Used gaps to predict elements not discovered yet 3) New elements fit into the gaps 4) Improved to become periodic table

11. The periodic table is arranged in periods and groups

    • 1) Rows called periods 2) Elements arranged increasing atomic number along each row 3) Period 2 elements increasse from 3 for lithium to 10 for neon
    • 1) Gropus coumns 2) Elements same group similar properties 3) Same number electrons outer shell 4) Group number same outer shell electrons