1. Indicator CCC Kei Heep Secondary School F.6 Chemistry by Wong CS Chemistry CE Homepage Chemistry AL Homepage

2. Type of Titration Strong acid + strong base Strong acid + weak base Weak acid + strong base Weak acid + weak base

3. Strong acid + strong base HCl (aq) + NaOH (aq)  NaCl (aq) + H 2 O (l) Both of indicators are suitable !

4. Strong acid + weak base HCl (aq) + NH 3 (aq)  NH 4 Cl (aq) Phenolphthalein is not suitable !

5. Weak acid + strong base CH 3 COOH (aq) + NaOH (aq)  NaCH 3 COO (aq) + H 2 O (l) Methyl orange is not suitable !

6. Weak acid + weak base CH 3 COOH (aq) + NH 3 (aq)  NH 4 CH 3 COO (aq) Neither phenolphthalein nor methyl orange is suitable !

7. Method of double indicators NaOH (aq) + HCl (aq)  NaCl (aq) + H 2 O (l) Na 2 CO 3 (aq) + HCl (aq)  NaCl (aq) + NaHCO 3 (aq) NaHCO 3 (aq) + HCl (aq)  NaCl (aq) + H 2 O (l) + CO 2 (g) Phenolphthalein is used for the equivalence point of NaOH, Methyl orange is used for the equivalence point of NaHCO 3.

8. End point Phenolphthalein : NaOH (aq) + HCl (aq)  NaCl (aq) + H 2 O (l) x mol Na 2 CO 3 (aq) + HCl (aq)  NaCl (aq) + NaHCO 3 (aq) y mol Methyl orange : NaHCO 3 (aq) + HCl (aq)  NaCl (aq) + H 2 O (l) + CO 2 (g) y mol

9. Purity Purity =