Edexcel A Level Chemistry:复习笔记5.5.1 Rates of Reaction
Rates of Reaction - Introduction The rate of reaction refers to the change in the amount or concentration of a reactant or product per unit time The units for rate of reaction are mol dm-3 s...
Edexcel A Level Chemistry:复习笔记5.4.4 Feasible Reactions
Feasible Reactions Graphing the Gibbs Equation The Gibbs equation can be expressed as the equation for a straight line ΔGꝋ = ΔHꝋ - TΔSꝋ ΔGꝋ = - ΔSꝋT + ΔHꝋ y = mx + c A graph of free energy ...
Edexcel A Level Chemistry:复习笔记5.4.3 Gibbs Free Energy
Feasibility of Reactions Gibbs free energy The feasibility of a reaction is determined by two factors The enthalpy and entropy change The two factors come together in a fundamental thermodyn...
Edexcel A Level Chemistry:复习笔记5.4.2 Entropy Calculations
Total Entropy Calculations If we take the reaction between sodium and chorine, we know that this is a very exothermic reaction and also involves a decrease in entropy as a solid is produced ...
四门AP物理学习内容有什么区别？应该如何选择？
作为AP科学类中的顶梁柱，AP物理可谓是撑起了科学类的半边天。但是新手小白在刚开始面对4门AP物理时总是傻傻分不清楚：这几门到底要学什么内容，彼此之间又有哪些异同？在选择的时候应该如何做好取舍呢？ AP物理...
Edexcel A Level Chemistry:复习笔记5.4.1 Introducing Entropy
Introducing Entropy You may have wondered why it is that endothermic reactions occur at all, after all, what can be the driving force behind endothermic reactions if the products end up in a...
Edexcel A Level Chemistry:复习笔记5.3.4 Enthalpy of Solution
Solution & Hydration Definitions Enthalpy of solution The standard enthalpy change of solution (ΔHsolꝋ) is the enthalpy change when 1 mole of an ionic substance dissolves in sufficient w...
Edexcel A Level Chemistry:复习笔记5.3.3 Polarising Power
Polarisation of Ions Theoretical lattice energies assume a perfect ionic model where the ions are 100% spherical and the attractions are purely electrostatic So overall, there has a been a c...
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...
