Zusammenfassung der Ressource
C1- States of Matter.
- The Particle Model
- Solids
- Strong force of attraction
- Fixed arrangement
- Regular lattice arrangement
- They vibrate in their position
- In their define shape and volume
- The hotter they get the more vibrations they do.
- Liquids
- Some force of attraction
- Dont keep a define shape as they flow in the bottom of the container
- If you cool it it will freeze and become a solid
- If you heat it, it will evaporate and become a gas.
- Gases
- No force of attraction
- Dont have a define shape
- Take the shape of the container
- Move constantly with random motion
- The hotter the gas= the faster they move
- They will either expand or their pressure would increase when heated
- They would condense if they cool down and then become a liquid
- Physical change
- They can go through to a different state of matter and go back to the original state
- Chemical change
- This is hard to reverse, as bonds between atoms break and the atoms change places- the atoms from the substances you start off with rearrange themselves to form different products
- Atomic structure
- John Dalton
- 19th century
- Described atoms as solid spheres and that sphere made up different elements.
- J.J Thomson
- Plum Pudding Model
- Atoms are made up of electrons
- Rutherford
- 1909
- Conducted the gold foil experiment with students Geiger and Marsden
- They fired positive alpha particles at a thin sheet of gold.
- They found out that some of the particles did go straight through. However, some was deflected more than expected and small number were deflected BACKWARDS.
- His theory: The Nuclear Atom. In this there is a positive charged nucleus at the centre surrounded by a cloud of electrons
- Bohr
- Suggested that electrons can only exist in fixed orbits and not anywhere in between. This was supported by many experiments.
- Isotopes are atoms with different numbers of neutrons
- Negative ions form when atoms gain electrons
- Positive ions form when atoms lose electrons