Chemistry - Formulae and Equations

• What 7 elements are diatomic ?

  Hydrogen

  Oxygen

  Fluorine

  Chlorine

  Iodine

  Bromine

  Nitrogen
• What is this

  PO4-3

  Phosphate
• What is the oxidation state the same as?

  The charge
• Where might the OS been found

  In front of the element symbol in roman numerals
• What does a increase in oxidation state mean

  It has oxidised / reducing agent
• What does a reduction in oxidation state mean

  It’s a reduction - oxidation agent
• When will a compound have a charge?

  If its in an aqueous solution
• What ions called when they don’t change in a reaction?

  Spectator ions
• How do you determine the oxidation state of an element

  The group its in

  The other elements present
• What does a element turn when it is reduced

  More negative
• What does a element turn when it is oxidised

  More positive
• what is reduction - not in terms of electrons

  Removal of oxygen

  Addition of hydrogen
• What is oxidation - not in terms of electrons

  Addition of oxygen

  Removal of hydrogen
• What is SO4^2-

  Sulphate
• What is S^2-

  Sulphide
• What is CO3^-

  Carbonate
• What is HCO3^-

  Hydrogen carbonate
• What is OH-

  Hydroxide
• What is NO3-

  Nitrate
• What is NH4-

  Ammonium
• What can an iconic equation be - examples?

  Precipation

  Neutralisation

  Displacement
• What are the 7 rules of oxidation numbers/states

  1. all uncombined elements must have an ON of 0

  2- the sum of ON in a compound is 0

  3- in an ion , the sum is equal to the overall charge

  4- the ON of group 1 is usually +1/ the ON of group 2 is +2

  5- the ON of group 7 is usually -1 / the ON of group 6 is -2

  6- the ON of oxygen is always -2 expect in peroxides or when added to fluorine

  7- the ON of hydrogen is +1 except in metal hydrides
• What is an oxidation state/number of a element?

  The number of electrons that are needed to be added or taken away from that element to make it neutral
• What do non-metals form ( ions)

  Negative ions

  Their group number -8 = the charge
• What do metals form ( ions)

  Positive ions corresponding to their group number
• What does a non-metal bonded with oxygen create?

  A negative ion

  -ate ending
• What does the ending of non-metals change to when bonded?

  • ide
• What is an element?

  A substance with only one type of atom
• What is a compound

  Two or more different elements chemically bonded together
• What is a molecule?

  2 or more different atoms bonded together

  Same or different element

  Smallest fundamental unit
• What is an ion

  An atom or a group of atoms that holds a negative or positive charge
• What is an atom

  Smallest part of an element that can exists

  Nucleus/ protons/nerutoons/electrons