Edexcel A Level Chemistry:复习笔记5.3.2 Born-Haber Cycles
Born-Haber Cycles A Born-Haber cycle is a specific application of Hess’ Law for ionic compounds and enable us to calculate lattice enthalpy which cannot be found by experiment The basic prin...
Edexcel A Level Chemistry:复习笔记5.3.1 Lattice Energy
Lattice Energy Lattice energy As with bond enthalpy, lattice energy (ΔHlattꝋ) can be expressed as a formation or dissociation process As a formation process, it is the enthalpy change when 1...
Edexcel A Level Chemistry:复习笔记5.2.8 Weak Acid - Strong Base Titration
Weak Acid - Strong Base Titration In this example, strong sodium hydroxide, NaOH (aq), is being added to weak ethanoic acid, CH3COOH (aq) NaOH (aq) + CH3COOH (aq) → CH3COONa (aq) + H2O (l) T...
Edexcel A Level Chemistry:复习笔记5.2.7 Buffers
Action of a Buffer Solution A buffer solution is a solution which resists changes in pH when small amounts of acids or alkalis are added A buffer solution is used to keep the pH almost const...
Edexcel A Level Chemistry:复习笔记5.2.6 Titration Curves
Drawing & Interpreting Titration Curves During a titration a pH meter can be used and a pH curve plotted A pH curve is a graph showing how the pH of a solution changes as the acid (or ba...
Edexcel A Level Chemistry:复习笔记5.2.5 Measuring and Comparing pH
Measuring and Comparing pH Strong and weak acids The relative strengths of different acids can be determined by measuring the pH of equimolar aqueous solutions of the acids, at the same temp...
Edexcel A Level Chemistry:复习笔记5.2.4 Ionic Product of Water
Ionic Product of Water, Kw In all aqueous solutions, an equilibrium exists in water where a few water molecules dissociate into protons and hydroxide ions We can derive an equilibrium consta...
Edexcel A Level Chemistry:复习笔记5.2.3 Acid Strength
Acid Dissociation Strong acids A strong acid is an acid that dissociates almost completely in aqueous solutions HCl (hydrochloric acid), HNO3 (nitric acid) and H2SO4 (sulfuric acid) The posi...
Edexcel A Level Chemistry:复习笔记5.2.2 pH
Defining pH The acidity of an aqueous solution depends on the number of H+ ions in solution The pH is defined as: pH = -log[H+] where [H+] is the concentration of hydrogen ions in mol dm–3 S...
