C5

No. of Moles = Mass(g) / Molar Mass(g) (relative formular mass) 

Mass = No. of Moles X Molar Mass

Molar Mass = Mass / No. of Moles

Empirical formulae (e.g. C6H1206 = CH2O)

Concentration = Moles / Volume (dm^3)

Moles = concentration X Volume

Volume = moles / concentration 

cm^3 / 1000 = dm^3

g/dm / Molar mass = mol/dm^3

Electrolysis is the decomposition of the liquid eletolyte, by passing a current through it. Moving ions transfer charge in the eletrolyte whilst electrons transfer charge in the wire.

+ions (Cation) accept electrons at the cathode and are discharged, they then move through the eletolyte and transfer charge. The now -ions (anion) are now attracted to the Anode where they give up the electrons before becoming discharged in to the eletrolyte again. 

• Anode - + electrode
• Anion - - Ions (onions, crying, sad, negative)
• Cathode - -electrode
• Cation - +ions (pussytive)

H+ and OH- are always present in aq. solutions. 

Mass gained at Cathode = Mass lost at Anode

AN OILRIG CAT

ANode Oxidation Is Loss Reduction Is Gain Cathode

Metal ions (& hydrogen) are positive

non-Metal ions are negative

Q=IT          (Charge = Current X Time)

Amount deposited on Cathode (removed from Anode) increases proportionaly with both time and current.

Titration allows you to measure the amount of a substance present in a solution

Titration curve: Equivalence point = neutralisation point = 25cm^3, Acid to Alkali

 Titre = volume needed to neutralise 

Measured using

• Gas syringe
• Upturned burette filled with water
• Upturned measuring cylinder filled with water

Reactions stop when one of the reactants is used up. The reactant used up first is called the limiting reactant, the other/s is called the excess

A mole of gas at room temperature and pressure has a volume of 24dm^3

Volume (dm^3) = number of moles X 24

Equilibria = reversible reactions – forward and backward reactions are equal Equilibrium = reversible reactions proceeds at the same rate in a closed system Reactants ............ concentration is greater then reactants       - Equilibrium - Right Concentration is greater then product ............ products           - Equilibrium - Left Add more product or remove reactant - reaction shifted to the left Remove product or add more reactant - reaction shifted to the right Increasing pressure moves equilibrium to the side with the least no. of moles of gas

Acids ionise in water to produce hydrogen ions (H+). 

Strong acids

• higher electrical conductivity (more H+ available to carry charge)
• Produces gas rapidly when reacting with magnesium or calcium carbonate (higher concentration of H+ causes more collisions between acid and ^)
• Lower pH (the higher the H+ the lower the pH
• Higher concentration of hydrogen ions
• Ionises completely in water to form ions and no molecules are present

Weak acids - (opposite to strong)

• Ionises slightly in water and produces an equilibrium mix containing acid molecules and ions