Section 1- Principles of Chemistry (part 1)

Section 1- Principles of Chemistry (part 1)

1. States of Matter

   • Solid
     • Very dense
     • Low energy
     • Vibrate
     • Regular arrangement
   • Liquid
     • Not as dense
     • Bigger gaps
     • Irregular arrangement
     • Higher energy
     • Able to move
   • Gas
     • Very low density
     • Random arrangement
     • Spread out+large gaps
     • High energy
     • Can be compressed

2. Movement of Particles

   • Diffusion is the movement of particles in liquids and gasses
   • Diffusion happens quicker in warm liquids because the particles have more energy
   • Solids don't diffuse because they are tightly packed together and so can only vibrate
   • Potassium Manganate and water
   • Ammonia and hydrogen chloride
   • Bromine gas and air

3. Atoms

   • The Nucleus
     • Protons and neutrons
     • Positive charge
     • Almost the whole mass of the atom is in the nucleus
     • Protons and electrons are the same amounts, just one is positive and one is negative
   • The Electrons
     • High energy
     • Nagatively charged
     • Very small mass
   • Atomic number= number of protons and electrons
   • Atomic mass= number of protons+ neutrons
   • Number of neutrons= Atomic number - Atomic mass
   • Molecules are groups of atoms

4. Elements, compounds and mixtures

   • Elements consist of one type of atom only
     • E.g Gold or Iron
   • Compounds are made of 2 or more types of atoms chemically bonded together
     • E.g Carbon Dioxide
   • Mixtures are similar to compounds but are not chemically bonded, they can be separated easily
     • E.g Air (mixture of gasses- nitrogen, oxygen, carbon dioxide ect)

5. Crystalisation

   • Used to separate a soluble solid from a solution
   • E.g You can separate rock salt from water by using filtration then evapourating the water to separate the soluble salt from water

6. Chromatography

   • Helps separate inks and dyes
   • Can be used by forensic scientists for blood or for farmers soil
   • Paper Chromatography
     • Draw line near bottom of paper
       • Add dots of dyes/inks
         • place bottom of chromatography paper in water
           • when the ink stops moving up the paper it is called the solvent front

7. Distillation

   • Simple distillation is for separating solutions
   • Fractional distillation is for separating a mixture of liquids
   • Can be used to separate ink from water

8. Filtration

   • Used to separate an insoluble solid from a liquid
   • E.g Sand and water

9. The Periodic Table

   • Dmitri Mendeleev- 1869
     • Arranged elements in order of atomic mass
   • Elements in a group have the same number of outer electrons+similar properties

Imagens e arquivos do mapa