Acids.

Acid: When the acid is added to water it releases H+ ions, therefore it is a proton donor.

Alkalis: A type of base that when dissolved in water releases OH- ions.

Strong acid: Acids that fully dissociate.

Weak acid: Acids that only partially dissociate.

Salts: When the H+ ion of an acid is replaced by a metal ion or NH4+

Acid + Carbonate ---> Salt + Carbon Dioide + Water

Acid + Base ---> Salt + Water

Acid + Alkali ---> Salt + Water

NH3 + HNO3 ---> NH4NO3

In ionic equations, only the reacting particles are included. 

• Solids never split.
• Acids always split.
• Solutions always split , (acid salts).
  
• Water and atoms never split.

Hydrated: A chrystalline form that contains water molecules.

Anhydrous: A substance that contains no water molecules.

Water of crystallisation: Water molecules that form an essential part of the crystalline structure of the compound.

The empirical formula of the compound is separated from the water of crystallisation by a dot.

1. Work out the mass of the anhydrous.               3. This is the Mr of the water.

2. Work out the mass of the water.                       4. Divide by the Mr of the water = 

3. Work out the empirical formula.                         number of water molecules.

 3. Take the overall Mr from the Mr of the solid.

Step 1: Weigh an empty crucible

Step 2: Add the hydrated salt into the weighed crucible. Weigh the crucible and the hydrted salt.

Step 3: Using a pipe-clay traingle, support the crucibe containing the hydrated salt on a tripod. Heat the crucible and contents gently for about one minute. Then heat it strongly for a further three minutes.

Step 4: Leave the crucible to cool. Then weigh the crucible and anhydrous salt.

• If the hydrated and anhydrous forms are similar colours or you can only see the surface of the crystals then some water could be left inside. A good soution is to heat to a constant mass. 
• Many salts decompose further when heated, tis can be very difficult to judge if there is no colour change.

1. Add a measured volume of one solution to a conical flask using a pipette.

2. Add the other solution to a burette and record the initial burette reading.

3. Add a few drops of an indicator to the solution in the conical flask.

4. Run the solution in the burette into the solution in the concial flask, swirling the conical flask throughout to mix the two solutions. Eventually the indicator changes colour at the end point of the titration. The end point is used to indicate the volume of one solution that exactly reacts with the volume of the second solution.

5. Record the final burette reading. The volume of solution added from the burette is called the titre, which is calculated by subtracting the initial from the final burette reading.

6. A quick, trial is carried out first to find the approximate titre.

7. The titraion is then repeated accurately, adding the solution dropwise until the end point is approached. Further titrations are carried out until two accurate titres are concordant.

1. Work out the moles of acid n= (C * V)/1000

2. Write out the balanced equation.

3. Find the moles of the substance you want to identify.

4. Scale up if necassary.

5. Find the mass of the unknown.

6. Use the formula of the unknown eg. (X2CO3) to find the Mr, n=m/Mr

7. Identify the substance using the periodic table.

Redox reaction: A reaction where both oxidation and reduction takes place.

• Oxidation is an increase in oxidation number or when a species loses electrons.
• Reduction is a decrease in oxidation number or when a species gains electrons.

• A reducing agent reduces another species.
• An oxidation agent oxidises another species.

Elements in a reaction that don't change in oxidation number are called spectator species.