📚 A-Level CIE Chemistry: Final Revision Outline | A-Level CIE 化学：期末复习提纲
This revision guide consolidates the most essential topics tested in the CIE A-Level Chemistry syllabus, covering both AS and A2 content. It is designed to help you quickly check key definitions, concepts, equations, and common exam pitfalls before your final assessment.
本复习提纲涵盖 CIE A-Level 化学课程中最核心的考点，兼顾 AS 和 A2 内容。旨在帮助你在期末考前快速回顾关键定义、概念、方程式和常见失分点。
1. Atomic Structure and Periodicity | 原子结构与周期性
All matter is composed of atoms, which consist of a nucleus containing protons and neutrons, surrounded by electrons in defined energy levels or shells. The atomic number Z equals the number of protons; the mass number A is the sum of protons and neutrons. Isotopes are atoms of the same element with different numbers of neutrons, hence different mass numbers. The relative atomic mass Aᵣ is the weighted average mass of an atom compared to 1/12th the mass of a carbon-12 atom.
物质由原子组成，原子核包含质子和中子，核外电子在特定的能级或电子层中运动。原子序数 Z 等于质子数；质量数 A 是质子数与中子数之和。同位素指质子数相同而中子数不同的原子，因此质量数不同。相对原子质量 Aᵣ 是元素所有同位素原子的加权平均质量与一个碳-12 原子质量的 1/12 的比值。
Periodicity refers to the repeating trends in physical and chemical properties across a period. Across Period 3, atomic radius decreases due to increasing nuclear charge pulling electrons closer. First ionisation energy generally increases, but with drops between Groups 2 and 3 (e.g., Be → B) and between Groups 5 and 6 (e.g., N → O) due to electron orbital stability and repulsion effects. Melting points peak at the giant covalent structure of silicon before dropping sharply at molecular elements like phosphorus, sulfur, and chlorine.
周期性指元素性质在同一周期中呈现规律性递变。第三周期从左到右，原子半径减小，因为核电荷增大使得电子被拉得更紧。第一电离能总体升高，但在第2族和第3族之间（如 Be → B）以及第5族和第6族之间（如 N → O）出现下降，这是由于轨道稳定性和电子排斥效应造成的。熔点方面，硅为巨型共价结构达到最高值，随后在磷、硫、氯等分子晶体处急剧下降。
2. Chemical Bonding and Structure | 化学键与结构
Ionic bonding occurs between metals and non-metals via electron transfer, forming a giant ionic lattice with strong electrostatic attraction between oppositely charged ions. Properties include high melting points, brittleness, and electrical conductivity only when molten or dissolved. Covalent bonding involves the sharing of electron pairs between non-metallic atoms. Molecules can be simple molecular with weak intermolecular forces (low boiling points) or giant covalent networks such as diamond, graphite, and silicon dioxide, which are extremely hard and have very high melting points. Metallic bonding consists of a lattice of positive metal ions surrounded by a ‘sea’ of delocalised electrons, explaining high electrical and thermal conductivity and malleability.
离子键通过金属和非金属之间的电子转移形成，构成巨型离子晶格，正负离子间存在强烈的静电引力。特性包括高熔点、脆性，以及只在熔融或溶解时导电。共价键通过非金属原子间共用电子对形成。分子可以是简单分子，由弱分子间作用力维系（沸点低），也可以是巨型共价网络，如金刚石、石墨和二氧化硅，质地极硬，熔点极高。金属键由正金属离子浸没在“电子海”中构成，能解释高导电、导热性和延展性。
Shapes of molecules are predicted by VSEPR theory: linear (e.g., CO₂, 2 bonding pairs, 180°), trigonal planar (e.g., BF₃, 3 BP, 120°), tetrahedral (e.g., CH₄, 4 BP, 109.5°), trigonal bipyramidal (e.g., PCl₅, 5 BP, 120° and 90°), octahedral (e.g., SF₆, 6 BP, 90°), and variations with lone pairs such as bent (H₂O, 104.5°) and trigonal pyramidal (NH₃, 107°). Electronegativity differences determine bond polarity and overall molecular dipole moment.
分子的空间构型根据价层电子对互斥理论预测：直线形（如 CO₂，2 对成键电子，180°）、平面三角形（如 BF₃，3 对，120°）、正四面体形（如 CH₄，4 对，109.5°）、三角双锥形（如 PCl₅，5 对，120° 和 90°）、正八面体形（如 SF₆，6 对，90°），以及含孤对电子的变体如 V 形（H₂O，104.5°）和三角锥形（NH₃，107°）。电负性差异决定了键的极性和分子的整体偶极矩。
3. Stoichiometry and the Mole | 化学计量与摩尔
The mole is the SI unit for amount of substance. One mole contains exactly 6.022 × 10²³ elementary entities (Avogadro constant). The molar mass M of a substance is the mass per mole, numerically equal to the relative formula mass. Key equations: n = m / M, concentration c = n / V, and for gases at room temperature and pressure (RTP, 20 °C, 1 atm), molar volume Vₘ ≈ 24.0 dm³ mol⁻¹, so n = V(gas) / 24.0 or use the ideal gas equation pV = nRT, where R = 8.31 J K⁻¹ mol⁻¹, p in Pa, V in m³, T in K.
摩尔是物质数量的国际单位。1 摩尔精确包含 6.022 × 10²³ 个基本单元（阿伏伽德罗常数）。物质的摩尔质量 M 是每摩尔的质量，数值上等于相对式量。核心公式：n = m / M，浓度 c = n / V，对于常温常压（RTP，20 °C，1 atm）下的气体，摩尔体积 Vₘ ≈ 24.0 dm³ mol⁻¹，所以 n = V(气体) / 24.0，或使用理想气体状态方程 pV = nRT，其中 R = 8.31 J K⁻¹ mol⁻¹，p 为帕斯卡，V 为立方米，T 为开尔文。
Empirical formula is the simplest whole-number ratio of atoms in a compound; molecular formula gives the actual number of atoms. Percentage yield = (actual yield / theoretical yield) × 100%. Atom economy = (mass of desired product / total mass of all products) × 100%. Limiting reagents must be identified to calculate theoretical yield. Water of crystallisation can be determined by heating a hydrated salt to constant mass and calculating the mole ratio of salt to water lost.
经验式（最简式）表示化合物中各原子最简整数比；分子式给出实际原子数目。产率百分比 = (实际产量 / 理论产量) × 100%。原子经济性 = (目标产物质量 / 所有产物总质量) × 100%。计算理论产量前必须确定限量反应物。结晶水含量可通过将水合盐加热至恒重，并计算无水盐与失去水的摩尔比来确定。
4. Energetics and Thermochemistry | 能量学与热化学
Enthalpy change ΔH is the heat energy transferred at constant pressure. Exothermic reactions release energy (ΔH negative); endothermic reactions absorb energy (ΔH positive). Standard conditions are 298 K, 100 kPa, and 1 mol dm⁻³ for solutions. Standard enthalpy changes include formation ΔH⁰_f, combustion ΔH⁰_c, neutralisation ΔH⁰_neut, and reaction ΔH⁰_r. Hess’s Law states that the total enthalpy change for a reaction is independent of the pathway, enabling calculations via known enthalpy changes of formation or combustion.
焓变 ΔH 是恒压下传递的热量。放热反应释放能量（ΔH 为负）；吸热反应吸收能量（ΔH 为正）。标准条件为 298 K、100 kPa，溶液浓度为 1 mol dm⁻³。标准焓变包括生成焓 ΔH⁰_f、燃烧焓 ΔH⁰_c、中和焓 ΔH⁰_neut 和反应焓 ΔH⁰_r。赫斯定律指出，反应的焓变总值与路径无关，因此可利用已知的生成焓或燃烧焓进行计算。
Bond enthalpies (average values) can be used to estimate ΔH: ΔH ≈ Σ(bond enthalpies broken) – Σ(bond enthalpies made). This method is less accurate because average bond enthalpies are not specific to a particular compound’s environment. Lattice energy is the enthalpy change when one mole of an ionic solid is formed from its gaseous ions. Born–Haber cycles link lattice energy to formation enthalpy, ionisation energies, electron affinities, and atomisation enthalpies. Enthalpy of solution and hydration determine solubility.
键焓（平均值）可用于估算 ΔH：ΔH ≈ Σ(断裂键的键焓) – Σ(生成键的键焓)。因平均键焓不针对具体分子环境，此法精度较低。晶格能是 1 摩尔离子固体由气态离子形成时的焓变。玻恩-哈伯循环将晶格能与生成焓、电离能、电子亲和能和原子化焓联系起来。溶解焓和水合焓共同决定溶解性。
ΔH = ΣΔH⁰_f(products) – ΣΔH⁰_f(reactants)
5. Kinetics | 反应动力学
Reaction rate is the change in concentration of a reactant or product per unit time, influenced by concentration, pressure (for gases), temperature, surface area, and catalysts. Collision theory states that for a reaction to occur, particles must collide with sufficient energy (greater than or equal to the activation energy Eₐ) and with correct orientation. Increasing temperature increases the proportion of particles with energy greater than Eₐ significantly, as shown by the Maxwell–Boltzmann distribution.
反应速率指单位时间内反应物或产物浓度的变化，受浓度、压强（对气体）、温度、表面积和催化剂影响。碰撞理论指出，反应发生要求粒子发生碰撞，且碰撞能量不低于活化能 Eₐ，取向合适。升高温度显著增大能量超过 Eₐ 的粒子比例，这可以通过麦克斯韦-玻尔兹曼分布说明。
Catalysts provide an alternative reaction pathway with a lower activation energy, thereby increasing the rate without being consumed. Homogeneous catalysts are in the same phase as the reactants; heterogeneous catalysts are in a different phase (e.g., solid catalyst for gaseous reactants). Enzymes are biological catalysts with highly specific active sites. Rate equations and order of reaction with respect to individual reactants are determined experimentally, leading to the rate constant k. For a reaction aA + bB → products, rate = k[A]ᵐ[B]ⁿ, where m and n are orders, not necessarily equal to stoichiometric coefficients.
催化剂提供活化能更低的替代反应路径，从而加快反应速率而自身不被消耗。均相催化剂与反应物处于同一相态；多相催化剂处于不同相态（如固体催化剂催化气体反应物）。酶是具有高度特异性活性位点的生物催化剂。速率方程及各反应物的反应级数由实验测得，导出速率常数 k。对于反应 aA + bB → 产物，速率 = k[A]ᵐ[B]ⁿ，其中 m 和 n 为级数，不一定等于化学计量系数。
6. Chemical Equilibria | 化学平衡
Dynamic equilibrium is reached in a closed system when the rates of the forward and reverse reactions are equal, and concentrations of reactants and products remain constant. Le Chatelier’s principle states that if a system at equilibrium is subjected to a change in concentration, pressure, or temperature, the equilibrium position shifts to oppose the change. Increasing temperature favours the endothermic direction; increasing pressure favours the side with fewer moles of gas. Catalysts do not alter equilibrium position but help reach equilibrium faster.
当可逆反应在密闭系统中正反应速率与逆反应速率相等，反应物和产物浓度不变时，达到动态平衡。勒夏特列原理指出，若平衡系统受到浓度、压强或温度变化的影响，平衡将向减弱这种改变的方向移动。升高温度有利于吸热方向；增大压强有利于气体分子总数较少的一方。催化剂不改变平衡位置，但能加快达到平衡的速率。
The equilibrium constant Kc is expressed in terms of concentrations: for aA + bB ⇌ cC + dD, Kc = [C]^c[D]^d / [A]^a[B]^b. Kp uses partial pressures in a similar expression. The magnitude of Kc indicates the extent of reaction: Kc >> 1 means products are favoured. The relationship between ΔG⁰ and equilibrium constant is ΔG⁰ = -RT lnK. Temperature is the only factor that changes the value of the equilibrium constant. The Haber process and Contact process are classic industrial examples of applying equilibrium principles.
平衡常数 Kc 以浓度表示：对于 aA + bB ⇌ cC + dD，Kc = [C]^c[D]^d / [A]^a[B]^b。Kp 使用分压的类似表达式。Kc 的大小反映反应进行的程度：Kc >> 1 表示平衡偏向产物。ΔG⁰ 与平衡常数的关系为 ΔG⁰ = -RT lnK。温度是唯一能改变平衡常数值的因素。哈伯合成氨和接触法制硫酸是应用平衡原理的典型工业实例。
Kc = ([C]^c[D]^d) / ([A]^a[B]^b)
7. Acids and Bases | 酸碱理论与计算
Lowry–Brønsted acids are proton donors; bases are proton acceptors. Strong acids (e.g., HCl, H₂SO₄, HNO₃) fully dissociate in water; weak acids (e.g., CH₃COOH) partially dissociate, establishing an equilibrium with an acid dissociation constant Kₐ. pKₐ = -log₁₀ Kₐ; the smaller the pKₐ, the stronger the acid. Water self-ionises: H₂O ⇌ H⁺ + OH⁻, with ionic product K_w = [H⁺][OH⁻] = 1.0 × 10⁻¹⁴ mol² dm⁻⁶ at 298 K.
根据布朗斯特-劳里理论，酸是质子给体，碱是质子受体。强酸（如 HCl、H₂SO₄、HNO₃）在水中完全离解；弱酸（如 CH₃COOH）部分离解，建立平衡并由酸离解常数 Kₐ 描述。pKₐ = -log₁₀ Kₐ；pKₐ 越小，酸性越强。水发生自耦电离：H₂O ⇌ H⁺ + OH⁻，离子积 K_w = [H⁺][OH⁻] = 1.0 × 10⁻¹⁴ mol² dm⁻⁶（298 K 时）。
pH = -log₁₀ [H⁺]; for strong monoprotic acids, [H⁺] equals acid concentration. For weak acids, [H⁺] = √(Kₐ × c). Buffer solutions resist changes in pH and consist of a weak acid and its conjugate base, or a weak base and its conjugate acid. The Henderson–Hasselbalch equation can be applied: pH = pKₐ + log₁₀([salt]/[acid]). Acid–base titrations produce characteristic pH curves; the equivalence point pH determines suitable indicators (e.g., phenolphthalein for strong acid–strong base, methyl orange for strong acid–weak base).
pH = -log₁₀ [H⁺]；对于一元强酸，[H⁺] 等于酸的浓度。对于弱酸，[H⁺] = √(Kₐ × c)。缓冲溶液能抵抗 pH 变化，由弱酸及其共轭碱或弱碱及其共轭酸组成。可使用 Henderson–Hasselbalch 方程：pH = pKₐ + log₁₀([盐]/[酸])。酸碱滴定产生特征 pH 曲线；等当点的 pH 决定合适的指示剂（如强酸强碱滴定用酚酞，强酸弱碱滴定用甲基橙）。
8. Redox and Electrochemistry | 氧化还原与电化学
Oxidation is the loss of electrons; reduction is the gain of electrons (OIL RIG). Oxidation numbers are assigned to atoms to track electron transfer. A redox reaction involves simultaneous oxidation and reduction. Half-equations show electron transfer explicitly. Disproportionation is a reaction in which an element simultaneously undergoes both oxidation and reduction (e.g., Cl₂ + 2OH⁻ → Cl⁻ + ClO⁻ + H₂O).
氧化是失去电子，还原是得到电子（OIL RIG）。氧化数用于跟踪电子转移。氧化还原反应同时包含氧化过程和还原过程。半反应方程清楚展示电子转移。歧化反应是同一元素的原子同时被氧化和还原的反应（如 Cl₂ + 2OH⁻ → Cl⁻ + ClO⁻ + H₂O）。
Electrochemical cells convert chemical energy to electrical energy. A standard electrode potential E⁰ measures the tendency of a half-cell to undergo reduction relative to the standard hydrogen electrode. The cell potential E⁰_cell = E⁰(cathode) – E⁰(anode); for a spontaneous reaction, E⁰_cell > 0. The electrochemical series lists half-cells in order of decreasing E⁰ values (more positive = stronger oxidising agent). Fuel cells, such as the hydrogen–oxygen fuel cell, convert chemical energy directly into electricity with higher efficiency and only water as a by-product. Electrolysis uses electrical energy to drive non-spontaneous reactions: Faraday’s constant F = 96,500 C mol⁻¹, and the charge Q = I × t relates to moles of electrons.
电化学电池将化学能转化为电能。标准电极电势 E⁰ 衡量半电池相对于标准氢电极发生还原的趋势。电池电动势 E⁰_cell = E⁰(正极) – E⁰(负极)；自发反应时 E⁰_cell > 0。电化学序将半电池按 E⁰ 值递减排序（数值越正，氧化剂的氧化性越强）。燃料电池，如氢氧燃料电池，直接将化学能高效转化为电能，唯一的副产物是水。电解是利用电能驱动非自发反应：法拉第常数 F = 96,500 C mol⁻¹，通过电荷量 Q = I × t 与电子的摩尔数关联。
9. Inorganic Chemistry: Groups 2 and 17 | 无机化学：第2族和第17族
Group 2 elements (alkaline earth metals) show trends down the group: decreasing first ionisation energy, increasing reactivity, increasing solubility of hydroxides, and decreasing solubility of sulfates. Reactions with water produce metal hydroxides and hydrogen, with beryllium as an exception that does not react directly. Thermal stability of Group 2 carbonates and nitrates increases down the group because the smaller cation polarises the anion less, making it harder to decompose. Common uses include magnesium in alloys, calcium in cement, and barium sulfate as a medical imaging contrast agent.
第2族元素（碱土金属）从上到下变化规律：第一电离能递减，反应活性递增，氢氧化物溶解度递增，硫酸盐溶解度递减。与水反应生成金属氢氧化物和氢气，铍例外，不与水直接反应。第2族碳酸盐和硝酸盐的热稳定性从上到下增强，因为较小阳离子对阴离子的极化作用更弱，使其更难分解。常见用途包括镁用于合金，钙用于水泥，硫酸钡作为医学造影剂。
Group 17 (halogens) exist as diatomic molecules F₂, Cl₂, Br₂, I₂. Electronegativity, reactivity, and oxidising power decrease down the group. Displacement reactions occur when a more reactive halogen oxidises the halide ion of a less reactive halogen (e.g., Cl₂ + 2Br⁻ → 2Cl⁻ + Br₂). Halide ions react with concentrated sulfuric acid: chloride gives HCl gas, bromide gives HBr and then SO₂ and Br₂ via redox, iodide gives H₂S, SO₂, and I₂, showing increasing reducing power down the group. Silver nitrate test helps identify halide ions: AgCl (white, soluble in dilute NH₃), AgBr (cream, soluble in conc NH₃), AgI (yellow, insoluble in NH₃).
第17族卤素以双原子分子 F₂、Cl₂、Br₂、I₂ 形式存在。电负性、反应性和氧化能力从上到下递减。较活泼的卤素能从卤化物中置换出较不活泼的卤素（如 Cl₂ + 2Br⁻ → 2Cl⁻ + Br₂）。卤离子与浓硫酸反应：氯离子生成 HCl 气体，溴离子生成 HBr 后发生氧化还原得到 SO₂ 和 Br₂，碘离子则生成 H₂S、SO₂ 和 I₂，显示出还原性从上到下增强。硝酸银测试可鉴定卤离子：AgCl（白色，溶于稀氨水）、AgBr（奶油色，溶于浓氨水）、AgI（黄色，不溶于氨水）。
10. Introduction to Organic Chemistry | 有机化学导论
Organic chemistry is the study of carbon compounds. Hydrocarbons contain only carbon and hydrogen. Homologous series are families of compounds with the same functional group, general formula, and gradual change in physical properties. Nomenclature follows IUPAC rules: identify the longest carbon chain, number to give the lowest locants to substituents and functional groups, and use prefixes (alkyl groups, halogeno-) and suffixes (-ane, -ene, -ol, -al, -one, -oic acid). Isomerism includes structural isomerism (chain, position, functional group) and stereoisomerism (E/Z or cis–trans and optical).
有机化学研究碳化合物的化学。烃类只含碳和氢。同系列是具有相同官能团、通式和渐变的物理性质的一系列化合物。命名法遵循 IUPAC 规则：选择最长碳链为主链，从最靠近取代基或官能团一端开始编号使位次最小，使用前缀（烷基、卤代）和后缀（-烷、-烯、-醇、-醛、-酮、-酸）。异构现象包括构造异构（碳链异构、位置异构、官能团异构）和立体异构（E/Z 或顺反异构和旋光异构）。
Alkanes are saturated hydrocarbons with general formula CₙH₂ₙ₊₂, undergoing combustion and free-radical substitution with halogens (initiation, propagation, termination). Alkenes are unsaturated containing a C=C bond; they undergo electrophilic addition (e.g., with H₂, halogens, hydrogen halides, steam). Markovnikov’s rule predicts the major product when adding unsymmetrical reagents: the hydrogen attaches to the carbon with more hydrogens already. Addition polymers are formed from alkenes; poly(ethene), poly(propene), and PVC are common examples. Alcohols are classified as primary, secondary, or tertiary, and undergo oxidation: primary → aldehyde → carboxylic acid; secondary → ketone; tertiary resist oxidation.
烷烃为饱和烃，通式 CₙH₂ₙ₊₂，可发生燃烧反应及与卤素的自由基取代反应（链引发、链增长、链终止）。烯烃含 C=C 双键，属不饱和烃；发生亲电加成（如与 H₂、卤素、卤化氢、水蒸气加成）。马尔科夫尼科夫规则预测不对称试剂加成时氢加在含氢较多的碳上。烯烃可发生加聚反应；聚乙烯、聚丙烯和聚氯乙烯是常见例子。醇可分伯、仲、叔醇，氧化产物：伯醇 → 醛 → 羧酸；仲醇 → 酮；叔醇不易被氧化。
11. Organic Reaction Mechanisms | 有机反应机理
Mechanisms show the movement of electrons using curly arrows. Free-radical substitution (alkanes with halogens in UV light) proceeds via homolytic fission, producing highly reactive radicals. Electrophilic addition (alkenes) starts with the electrophile attacking the electron-rich double bond, forming a carbocation intermediate, then rapid attack by a nucleophile. Nucleophilic substitution is key for halogenoalkanes: S_N1 proceeds via a planar carbocation giving racemic mixture; S_N2 involves a direct backside attack leading to inversion of configuration. The rate depends on the class of halogenoalkane: tertiary favours S_N1, primary favours S_N2.
反应机理使用弯箭头表示电子转移。自由基取代（烷烃与卤素在紫外光下）通过均裂生成高活性自由基。亲电加成（烯烃）始于亲电试剂进攻富电子的双键，形成碳正离子中间体，随后被亲核试剂快速进攻。亲核取代是卤代烷的核心反应：S_N1 经过平面型碳正离子中间体，产物为外消旋混合物；S_N2 为背面直接进攻，导致构型翻转。速率取决于卤代烷的类别：叔卤代烷倾向于 S_N1，伯卤代烷倾向于 S_N2。
Carbonyl compounds (aldehydes and ketones) undergo nucleophilic addition with HCN, generating hydroxynitriles, which lengthens the carbon chain. Reduction with NaBH₄ or LiAlH₄ produces alcohols. The carbonyl group is planar, so nucleophilic attack occurs equally from either side, producing racemic mixture if a chiral centre is generated. Carboxylic acids and their derivatives (acyl chlorides, esters, amides) undergo nucleophilic acyl substitution. Identification tests: 2,4-DNPH for carbonyl groups (orange precipitate); Tollens’ reagent for aldehydes (silver mirror); acidified potassium dichromate(VI) colour change for oxidisable groups.
羰基化合物（醛和酮）与 HCN 发生亲核加成生成羟腈，使碳链增长。用 NaBH₄ 或 LiAlH₄ 还原可得醇。羰基是平面型的，亲核试剂从两面进攻的概率相等，若生成手性中心则得到外消旋混合物。羧酸及其衍生物（酰氯、酯、酰胺）发生亲核酰基取代。鉴别测试：2,4-二硝基苯肼检验羰基（橙黄色沉淀）；托伦试剂检验醛基（银镜反应）；酸化重铬酸钾(VI)检验可被氧化的基团（颜色由橙变绿）。
12. Analytical Chemistry and Spectroscopy | 分析化学与波谱
Infrared spectroscopy identifies functional groups through characteristic absorption peaks corresponding to bond vibrations. The fingerprint region (below 1500 cm⁻¹) is unique to each compound and can be matched against databases. Key absorptions: O–H (alcohols) broad around 3200–3600 cm⁻¹, C=O around 1700 cm⁻¹ (sharp, strong), C–O around 1000–1300 cm⁻¹.
红外光谱通过特征吸收峰鉴定官能团，吸收峰对应化学键的振动。指纹区（1500 cm⁻¹ 以下）是每种化合物特有的，可与数据库对照。关键吸收：O–H（醇）在 3200–3600 cm⁻¹ 左右有一宽峰，C=O 在 1700 cm⁻¹ 附近（尖而强），C–O 在 1000–1300 cm⁻¹ 区域。
Mass spectrometry gives the molecular ion peak (M⁺) for molecular mass and fragmentation patterns that provide structural clues. The highest m/z value (ignoring isotopes) typically corresponds to the parent ion. High-resolution mass spectrometry can determine molecular formula from precise mass. Proton NMR gives information about the number of chemically different hydrogen environments (number of peaks), the relative number of protons in each environment (integration ratio), and the neighbouring protons (splitting pattern, n+1 rule). Chemical shift δ values indicate the type of hydrogen environment. Carbon-13 NMR shows the number of different carbon environments. Combined spectral analysis allows for full structural determination.
质谱给出分子离子峰（M⁺）确定分子量，碎片峰提供结构线索。最高 m/z 值（不计同位素）通常对应母体离子。高分辨质谱可从精确质量确定分子式。质子核磁共振谱提供化学不等价氢环境的数量（峰数目）、各环境中氢原子的相对个数（积分比）和相邻氢原子的信息（裂分模式，n+1 规则）。化学位移 δ 值指示氢环境类型。碳-13 核磁共振谱显示不同碳环境的数目。综合波谱分析可实现完整结构解析。
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