Chemistry Chap. 1 - Atom Mid Topic Revision sheet

Chemistry Chap. 1 - Atom Mid Topic Revision sheet

1. Elements, Atoms, Compounds, Mixtures and Balancing Equations

   • Atoms
     • The Smallest unit of an Element
   • Compounds
     • 2 or more different element chemically combined together
       • Compounds are formed and can only be removed by Chemical Reactions
   • Mixtures
     • different substances, that aren't chemically combined together
   • Elements
     • a group of one type of atoms chemically combined together
   • Molecules
     • 2 or more atoms chemically combined together (they can be the same type or different)
   • Chemical Reactions
     • always involve the formation of one or more substances and usually involve detectable energy change
   • Word Equation Examples
     • Sulphur + Oxygen -> Sulphur Oxide
     • Sodium + Chlorine -> Sulphur Chloride
   • Monoxide
     • Is used for elements that can react with oxide in multiple ways
       • Monoxide
       • Dioxide
       • Trioxide

2. Mixtures

   • 4 methods of Separating Mixtures
     • Filtration
       • Filtration is a physical or chemical separation process that separates an insoluble matter and fluid from a mixture
     • Evaporation
       • the process of turning from liquid into vapour.
     • Chemotography
       • Used to find the different Chemicals in the ink of a particular pen
     • Distillation
       • Simple
         • Is used to separate liquids. E.g Salt Water and Water
       • Fractional
         • Is when many liquids together are to be separated

3. Subatomic particles and the atom

   • the atom contains 5 things
     • Neutron
       • This has a neutral Charge
     • Proton
       • Has a positive Charge
     • Shell
       • This has a negative charge due to it having only electrons
     • Electron
       • Has a negative Charge
     • Nuclues
       • has a postive charge though made of protons and neutrons as neutrons have no charge
         • there is no space between the shell and the nucleus
           • Atoms are extremely small as the typical radius of an atom is 10^-1 and the nucleus a radius of 10^-14 as most of the atoms mass comes from the nucleus
   • Calculating the right amount of subatomic particles in an atom
     • Relative mass number = no. of protons and neutrons
     • Atomic number = no. of protons
       • No. of protons = no. of electrons
     • To find the amount of neutrons you do
       • Relative atomic mass - atomic number

4. Relative formula mass and isotopes

   • Atoms are neutral overall as the amount of protons is the same amount of electrons so there is no charge overall
     • If you were to add an electron, the charge would be NEGATIVE
       • If you were to minus an electron the charge would Be POSITIVE
   • What is an Isotope
     • Atoms of the same element that have different relative atomic masses due to there being a difference in neutrons
       • All element have isotopes
       • The atomic mass on the periodic table is the average of all isotopes that is why Chlorines Relative Atomic Mss is 35.5
   • How do you calculate the Relative Atomic Mass
     • RAM = (% Abundance of isotope 1 x mass of isotope 1) + (%Abundance of isotope 2 x mass of isotope 2 ) / 100

5. Electric configuration

   • The first shell holds up to 2 electrons
     • All other shells hold up to 8 electrons
   • The number of electrons on the outer shell/ ring is determined by the group (on the periodic table) the element is in
     • The number of Shells in the electric Configuration is determined by what period ( on the periodic table) the element is in