📚 AQA AS/A-Level Chemistry Unit 5 Insert (June 2019): Key Data and Exam Technique | AQA AS/A-Level化学第五单元资料手册（2019年6月）：核心数据与应试技巧
The June 2019 AQA Chemistry Unit 5 insert is more than just a data sheet; it is a carefully organised toolkit for thermodynamics, electrochemistry and inorganic qualitative analysis. Understanding exactly where each block of data sits, what it means and how to apply it under timed conditions can make the difference between a solid B and an A*. This article explains the main sections of the insert, linked to the AQA legacy and international Unit 5 specification, and gives you a clear method for using the data efficiently in the exam.
2019年6月AQA化学第五单元资料手册不只是一张数据表，它是一套为热力学、电化学和无机定性分析精心设计的工具箱。清楚每一部分数据的所在位置、含义以及如何在限时考试中运用，可能是你从B提升到A*的关键。本文将对照AQA旧版及国际版第五单元考纲，说明资料手册的主要板块，并给你一套在考试中高效使用数据的清晰方法。
1. Overview of the Unit 5 Insert | 第五单元资料手册总览
The insert for Unit 5 typically contains a periodic table, standard electrode potentials, lattice enthalpy and hydration enthalpy data, entropy values, common ligand names and sometimes a colour chart for transition metal complexes. You should be able to find a value in under ten seconds, so always start by scanning the headings and memorising the layout.
第五单元资料手册通常包含周期表、标准电极电势、晶格焓和水合焓数据、熵值、常见配体名称，有时还有过渡金属配合物的颜色表。你应该能在十秒内找到一个数据，因此一开始就要浏览各标题并记住版面布局。
Electrode potentials are listed as reduction half-equations with E° values.
电极电势以还原半反应的形式列出，并给出E°值。
Thermodynamic values may be given for specific compounds, so check states and signs carefully.
热力学数据可能针对特定化合物给出，所以要仔细检查物态和正负号。
2. Reading Standard Electrode Potentials | 读取标准电极电势
means the oxidised form on the left is a stronger oxidising agent and the reduced form on the right is a weaker reducing agent.
资料手册中的标准电极电势总是写成还原半反应：氧化态 + ne⁻ → 还原态。E°值越正，说明左边的氧化态是越强的氧化剂，右边的还原态是越弱的还原剂。
inc is oxidised and copper(II) is reduced, giving a cell EMF of +0.34 - (-0.76) = +1.10 V.
例如，如果你看到E°(Zn²⁺/Zn) = -0.76 V，E°(Cu²⁺/Cu) = +0.34 V，那么铜(II)离子比锌(II)离子更容易被还原。在丹尼尔电池中，锌被氧化，铜(II)被还原，电池电动势为+0.34 - (-0.76) = +1.10 V。
e), where cathode and anode refer to the reduction half-equations as written in the table.
千万不要在相减之前改变E°的正负号。使用公式E°(电池) = E°(阴极) - E°(阳极)，其中阴极和阳极均按表中写的还原半反应来使用。
3. Predicting Feasibility of Redox Reactions | 预测氧化还原反应的自发性
A redox reaction is thermodynamically feasible under standard conditions if the calculated cell EMF is positive. For example, can acidified dichromate(VI) oxidise chloride ions? You would combine the half-equations for Cr₂O₇²⁻/Cr³⁺ and Cl₂/Cl⁻, using the correct E° values from the insert.
在标准条件下，如果计算出的电池电动势为正，则该氧化还原反应在热力学上是可行的。例如，酸化重铬酸根(VI)能否氧化氯离子？你需要结合资料手册中Cr₂O₇²⁻/Cr³⁺和Cl₂/Cl⁻的半反应及正确的E°值来判断。
-0.03 V. The negative value means the reaction is not feasible under standard conditions.
如果E°(Cr₂O₇²⁻/Cr³⁺) = +1.33 V，E°(Cl₂/Cl⁻) = +1.36 V，那么在重铬酸根氧化氯离子的反应中，电池电动势为+1.33 - (+1.36) = -0.03 V。负值说明该反应在标准条件下不可行。
However, a positive EMF does not guarantee a visible reaction because the activation energy may be too high or the conditions may be non-standard. Always mention kinetics as a limitation in explain questions.
然而，电动势为正并不保证能观察到反应，因为活化能可能过高或条件可能不是标准状态。在解释题中一定要提到动力学这一限制因素。
4. Using Born-Haber Cycle Data | 运用玻恩-哈伯循环数据
The insert may provide enthalpy changes such as standard enthalpy of formation, atomisation, ionisation energy, electron affinity and lattice enthalpy. A Born-Haber cycle links these values so you can calculate an unknown lattice enthalpy or electron affinity.
资料手册可能提供标准生成焓、原子化焓、电离能、电子亲和能和晶格焓等焓变。玻恩-哈伯循环将这些数值联系起来，使你能计算未知的晶格焓或电子亲和能。
s) (lattice enthalpy). The sum of these steps equals the enthalpy of formation of NaCl(s).
对于氯化钠，循环步骤为：Na(s) → Na(g)（原子化），Na(g) → Na⁺(g) + e⁻（第一电离能），½Cl₂(g) → Cl(g)（原子化），Cl(g) + e⁻ → Cl⁻(g)（电子亲和能），以及Na⁺(g) + Cl⁻(g) → NaCl(s)（晶格焓）。这些步骤之和等于NaCl(s)的生成焓。
Work systematically: draw the cycle first, label each arrow with the correct sign and state symbol from the insert, then solve the unknown by applying Hess's law.
要有条理：先画出循环图，用资料手册中正确的正负号和物态标注每个箭头，然后应用盖斯定律求解未知量。
5. Entropy, Gibbs Free Energy and Spontaneity | 熵、吉布斯自由能与自发性
hat ΔS° is given in J K⁻¹ mol⁻¹ while ΔH° is usually in kJ mol⁻¹, so convert one of them before calculating.
第五单元的题目常要求你利用资料手册中的数值计算标准熵变ΔS°，然后结合ΔH°通过公式ΔG° = ΔH° - TΔS°求出ΔG°。记住ΔS°的单位是J K⁻¹ mol⁻¹，而ΔH°通常是kJ mol⁻¹，因此计算前必须先统一单位。
temperature where ΔG° = 0, the reaction changes from non-spontaneous to spontaneous; this 'threshold temperature' can be found by rearranging to T = ΔH°/ΔS°.
当ΔG°为负时反应是自发的。在ΔG° = 0的温度下，反应从非自发变为自发；这个“临界温度”可以通过将公式变形为T = ΔH°/ΔS°来求得。
T = 180000/250 = 720 K. Above 720 K the reaction is feasible because ΔG° becomes negative.
例如，如果ΔH° = +180 kJ mol⁻¹，ΔS° = +250 J K⁻¹ mol⁻¹，先将ΔH°转换为180000 J mol⁻¹，然后T = 180000/250 = 720 K。高于720 K时反应可行，因为ΔG°变为负值。
6. Redox Titrations: Manganate(VII) and Iodine-Thiosulfate | 氧化还原滴定：高锰酸根(VII)与碘-硫代硫酸盐
The insert' titrations, MnO₄⁻ is reduced to Mn²⁺ in acidic solution: MnO₄⁻ + 8H⁺ + 5e⁻ → Mn²⁺ + 4H₂O.
资料手册中的电极电势表可以帮助你构建常见氧化还原滴定的半反应。对于高锰酸根(VII)滴定，MnO₄⁻在酸性溶液中被还原为Mn²⁺：MnO₄⁻ + 8H⁺ + 5e⁻ → Mn²⁺ + 4H₂O。
rall ratio is 1 mol MnO₄⁻ to 5 mol Fe²⁺. Use this ratio after finding moles of MnO₄⁻ from concentration and titre volume.
在铁(II)滴定中，Fe²⁺被氧化为Fe³⁺：Fe²⁺ → Fe³⁺ + e⁻。总反应比例为1 mol MnO₄⁻对应5 mol Fe²⁺。根据高锰酸根的浓度和滴定体积求出其物质的量后，再用这个比例计算铁的量。
atio is 1 mol I₂ to 2 mol S₂O₃²⁻. Always include the oxidation states in your answer to show electron transfer.
对于碘-硫代硫酸盐滴定，半反应I₂ + 2e⁻ → 2I⁻与2S₂O₃²⁻ → S₄O₆²⁻ + 2e⁻配对。比例为1 mol I₂对应2 mol S₂O₃²⁻。在答案中始终标明氧化态以显示电子转移。
7. Transition Metal Complexes and Colour Data | 过渡金属配合物与颜色数据
The Unit 5 insert often includes a colour chart for common aqueous transition metal ions and their complexes. For example, [Cu(H₂O)₆]²⁺ is blue, [Co(H₂O)₆]²⁺ is pink, and [Fe(H₂O)₆]³⁺ is yellow-brown. These colours appear in ligand substitution and precipitation questions.
第五单元资料手册通常包含常见水合过渡金属离子及其配合物的颜色表。例如，[Cu(H₂O)₆]²⁺为蓝色，[Co(H₂O)₆]²⁺为粉红色，[Fe(H₂O)₆]³⁺为黄棕色。这些颜色出现在配体取代和沉淀反应题中。
When ammonia is added dropwise to copper(II) sulfate solution, a pale blue precipitate of Cu(OH)₂ forms first. With excess ammonia, this dissolves to give a deep blue solution of [Cu(NH₃)₄(H₂O)₂]²⁺. Use the insert to confirm the charges and coordination numbers.
当氨水逐滴加入硫酸铜(II)溶液时，首先形成浅蓝色Cu(OH)₂沉淀。氨水过量时沉淀溶解，生成深蓝色的[Cu(NH₃)₄(H₂O)₂]²⁺溶液。利用资料手册确认电荷数和配位数。
Ligand substitution can also involve chloride ions. Adding concentrated HCl to copper(II) sulfate solution changes the blue colour to yellow-green as [CuCl₄]²⁻ forms. The insert usually lists the common ligands in order of increasing ligand field strength, which can help you predict colour shifts.
配体取代也可以涉及氯离子。向硫酸铜(II)溶液中加入浓盐酸，蓝色会变为黄绿色，因为生成了[CuCl₄]²⁻。资料手册通常按配体场强度递增的顺序列出常见配体，这有助于预测颜色变化。
8. Qualitative Inorganic Analysis | 无机定性分析
Unit 5 inserts often summarise tests for anions and cations, including flame tests and precipitation reactions. Sodium gives a yellow flame, potassium gives lilac, calcium gives brick-red, and barium gives apple-green. The insert may include these in a compact table.
第五单元资料手册常总结阴离子和阳离子的检验方法，包括焰色反应和沉淀反应。钠产生黄色火焰，钾产生淡紫色，钙产生砖红色，钡产生苹果绿色。资料手册可能以紧凑表格形式列出这些内容。
For halide ions, adding silver nitrate solution followed by dilute ammonia and concentrated ammonia distinguishes chloride, bromide and iodide. AgCl gives a white precipitate soluble in dilute ammonia; AgBr gives a cream precipitate soluble only in concentrated ammonia; AgI gives a yellow precipitate insoluble in concentrated ammonia.
对于卤素离子，加入硝酸银溶液，再分别加入稀氨水和浓氨水，可以区分氯离子、溴离子和碘离子。AgCl产生白色沉淀，溶于稀氨水；AgBr产生奶油色沉淀，只溶于浓氨水；AgI产生黄色沉淀，不溶于浓氨水。
Carbonate ions effervesce with dilute acid, giving CO₂ which turns limewater milky. Sulfate ions give a white precipitate with barium chloride acidified with HCl. Always mention the acidification step to eliminate carbonate and sulfite interference.
碳酸根离子与稀酸反应产生气体CO₂，使石灰水变浑浊。硫酸根离子与酸化后的氯化钡溶液产生白色沉淀。答题时一定要提到酸化步骤，以排除碳酸根和亚硫酸根干扰。
9. Worked Example: Using E° Values in a Cell Calculation | 实例分析：运用E°值进行电池计算
sked to calculate the standard cell EMF for the reaction between acidified manganate(VII) and iron(II) ions.
我们来看一道典型的第五单元计算题。题目给出资料手册中的还原电势：E°(MnO₄⁻/Mn²⁺) = +1.51 V，E°(Fe³⁺/Fe²⁺) = +0.77 V。要求计算酸化高锰酸根与铁(II)离子反应的标准电池电动势。
idation (anode). Calculate E°(cell) = E°(cathode) - E°(anode) = +1.51 - (+0.77) = +0.74 V.
高锰酸根半反应的E°更正，因此它是还原反应（阴极）。铁的半反应则反向进行，为氧化反应（阳极）。计算E°(电池) = E°(阴极) - E°(阳极) = +1.51 - (+0.77) = +0.74 V。
the end point is detected by the first permanent pink colour, which appears when excess MnO₄⁻ is present.
由于电池电动势为正，该反应在标准条件下热力学可行。总反应方程式为MnO₄⁻ + 8H⁺ + 5Fe²⁺ → Mn²⁺ + 4H₂O + 5Fe³⁺。在滴定中，终点通过首次出现的持久粉红色来判断，此时存在过量MnO₄⁻。
10. Common Mistakes When Using the Insert | 使用资料手册的常见错误
One common mistake is reversing the sign of an electrode potential before using the formula. The E° values in the table are reduction potentials; do not change the sign when assigning cathode and anode. Simply subtract the anode value from the cathode value.
一个常见错误是在使用公式前先改变电极电势的正负号。表中的E°值是还原电势；在确定阴极和阳极时不要改变正负号。只需用阴极值减去阳极值即可。
when using ΔG° = ΔH° - TΔS°. Always check the units before substituting into the equation.
另一个常见错误是在使用ΔG° = ΔH° - TΔS°时忘记将ΔS°从J K⁻¹ mol⁻¹转换为kJ K⁻¹ mol⁻¹，或将ΔH°从kJ mol⁻¹转换为J mol⁻¹。代入公式前务必检查单位。
Students also lose marks by citing electrode potential values without stating conditions, such as 298 K, 100 kPa and 1 mol dm⁻³. If the question asks about non-standard conditions, mention that the E° values may change and the prediction may no longer hold.
学生还会因为引用电极电势值时没有说明条件（如298 K、100 kPa和1 mol dm⁻³）而失分。如果题目涉及非标准条件，要提到E°值可能改变，预测可能不再成立。
11. How to Practise with the Insert | 如何利用资料手册进行练习
Print a clean copy of the June 2019 insert and try to complete a past paper using only that insert. Time yourself and note which data you could not locate quickly. Then create a personal 'data index' with the page number and a one-line description for each section.
打印一份干净的2019年6月资料手册，尝试只使用这份资料完成一套往年真题。计时并记录哪些数据你无法快速找到。然后制作一份个人“数据索引”，列出每个部分的页码和一行描述。
For thermodynamics questions, practise drawing Born-Haber cycles and labelling each arrow with the correct symbol and sign before looking at the numerical values. For redox questions, practise writing the two half-equations from the electrode potential table and combining them to give a balanced overall equation.
对于热力学题目，练习先画出玻恩-哈伯循环并标注每个箭头的正确符号和正负号，然后再看具体数值。对于氧化还原题目，练习从电极电势表写出两个半反应，并将它们合并为配平的总方程式。
Finally, make a one-page summary of the qualitative analysis tests and the transition metal colours, because these are the most frequently needed data in Unit 5 practical-style questions.
最后，制作一页定性分析检验和过渡金属颜色的总结，因为这些是第五单元实验类题目中最常需要的数据。
12. Final Exam Checklist | 考前最终清单
Before you enter the exam room, ensure you can answer yes to these questions: Can I locate any electrode potential within five seconds? Do I know the sign convention for E°? Can I convert between J and kJ in Gibbs calculations? Can I balance a redox equation using half-reactions from the insert?
进入考场前，确保你能对以下问题回答“是”：我能在五秒内找到任何电极电势吗？我知道E°
Published by TutorHao | AS Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
或截图后用「扫一扫 → 相册」选择本图