• Group: Groups are the columns of elements, elements in a group share physical and chemical properties because of their identical valence shells. There are 18 groups, however only 8 groups have unique valencies
• Period: Periods are the rows of elements, there are 7 groups. Elements in a period share the share the same number of electron shells
• As the atomic no. increases, the no. of electrons and shells increase
• Down a group:
  • Atomic radius increases
  • More electron shells are added
• Across a period:
  • Atomic radius decreases
  • More protons in the nucleus attract electrons more strongly
  • Electrons are pulled closer to the nucleus

metals & non-metals:

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Metals:

• High melting and boiling points

  • High intermolecular forces that require a lot of heat/energy

• Good conductors of heat and electricity

  • Electrons are free to move around

• Solid state at room temperature

• Malleable (easily shaped)

  • Layers of atoms can slip and slid over each other

• Ductile

• Lustrous (reflects light easily)

• Sonorous (makes ringing sound)

• High density and are hard and strong

  • Many atoms packed closely together

• 1-3 valence electrons

• Lose electrons easily

• From basic oxides

• Acts as a reducing agent as it gives electrons

• Forms positive ions </aside>

<aside>

Nonmetals:

• Low melting and boiling points

  • Weak intermolecular forces that need only little energy to break

• Poor conductors of heat and electricity

  • No free electrons are present in the lattice

• Solid, liquid or gas at room temperature

• Usually brittle (breaks easily)

  • weak attractive forces

• Non-ductile

• Non-lustrous

• Non-sonorous

• Low densities and are weak

  • Bonding between molecules are weak therefore there is high volume and low density

• 5-7 valence electrons

• Share or gain electrons easily

• Form acidic oxides

• Act as a oxidizing agent as it takes electrons

• Forms negative ions </aside>

Metallic bonding is the chemical bonding that takes place between atoms of the same metal. Metallic bonding occurs due to the electrostatic forces and nature of attraction of metal cations (positively charged ions) and the free flowing number of delocalized electrons. Metallic bonds have a very strong force of attraction between the atoms and as a result, large amounts of energy are required to break this bond. Hence, the melting point and boiling points of these bonded atoms are very high. The spaces between the cations allow for the movement of the delocalised electrons which allows atoms to conduct heat and electricity. The bonded atoms are arranged in organised layers which can slide over each other easily and therefore are malleable and ductile

metal extraction:

• Metals more reactive than carbon would be extracted using electrolysis because they are stable oxides in ores, and therefore can be reduced using a process called electrolysis (process of using electricity to split water into hydrogen and oxygen)

• Metals less reactive than carbon are extracted using carbon reduction because they are unstable oxides that exist in ores

  

groups:

Group 1 - Alkali Metals:

Group 1 elements have 1 electron in their outer shell, making them highly reactive, so they are normally stored in oil

Forms cations of +1

Properties:

• Good conductors
  • Have free moving electrons
• Soft and can be cut with a knife
  • Weak metallic binds with makes it softer
• Melting and boiling points decrease down the group
• Density generally increases down the group
• Reactivity increases down the group
• Reactivity time increases