P.1

• How big is a atom

  1 x 10-¹⁰
• John dalton

  Atoms in an element are the same

  Atoms differ in every element

  Atom is a solid ball
• JJ Thompson 


  Created the plum pudding model

  Discovered that there were electrons in the atom containing a positive charge
• Ernest Rutherford 


  Discovered the atom had a nucleus by shooting alpha particles at gold foil
• Who worked with Rutherford 


  Hans Geiger and Ernest Marsden
• Nihels Bhor 


  Discovered that electrons circulated the nucleus in shells

  Since other wise they would cirlcle into the nucles
• Solid 


  Fixed position

  Vibrate around a spot

  Regular shape
• Liquid 


  Randon shape

  Move around each other

  Take the shape of the container
• Gases 


  Fast moving particles

  Move freely

  Random shape
• Subliming 


  Solid -> Gas
• Depositing 


  Gas -> Solid
• Physical change 


  Something that can be reversible
• Chemical change 


  Usally something that is irreversible
• C° vs K°


  When C° = 0 K° = 273

  When K° = 0 C° = -273
• SHC


  tells you how much energy is needed to rais the temp by 1kg of material by one C°
• SLH - Fusion 


  Amount of energy transferred when 1kg of a substance changes from solid ⇌ liquid
• SLH - Vaporisation 


  Amount of energy transferred when 1kg of a substance changes from Liquid ⇌
• Gas pressure 


  Each collision produces a small force

  A bigger force = more collisions
• What is Pressure measured in 


  Pa (Pascals)

  1 Pa = 1N/m²

  1kPa = 1000 Pa
• When pressure increases volume decrease

  And vice versa
• Atmospheric pressure increases closer to the ground
• Liquid pressure

  Deeper you go in water the higher the pressure