📚 IB and CIE Chemistry: Practical Experiment Guide | IB CIE 化学：实验操作指南
Mastering practical skills is essential for success in both IB and CIE A-Level Chemistry. This guide covers core laboratory techniques, safety, data handling, and common experiments you are likely to encounter, with clear steps and explanations to build confidence in the lab.
掌握实验技能是 IB 和 CIE 化学取得好成绩的关键。本指南涵盖核心实验室技术、安全规范、数据处理以及你很可能遇到的常见实验，用清晰的步骤和解释帮助你在实验室中建立信心。
1. Laboratory Safety and Good Practice | 实验室安全与规范
Always wear safety goggles and a lab coat. Tie back long hair and remove dangling jewellery. Work in a well-ventilated space and know the location of the eye-wash station, fire extinguisher, and first-aid kit.
始终佩戴护目镜和实验服。将长发束起，取下悬垂的首饰。在通风良好的区域操作，并知晓洗眼器、灭火器和急救箱的位置。
Never taste or directly smell chemicals. When you need to detect an odour, gently waft the vapour towards your nose. Label all containers clearly and never return unused reagents to stock bottles to avoid contamination.
切勿品尝或直接嗅闻化学品。需要闻气味时，用手轻轻扇动气体朝向鼻子。所有容器要贴好标签，切勿将剩余试剂倒回原瓶以防污染。
Dispose of waste as instructed: aqueous solutions may be diluted and poured down the sink, while organic solvents and heavy-metal residues require special waste containers. Broken glass goes into the sharps bin.
按指导处理废弃物：水溶液可稀释后倒入水槽，有机溶剂和重金属残留物要放入专用废液桶。碎玻璃放入锐器收集盒。
2. Measurement, Uncertainty, and Significant Figures | 测量、不确定度与有效数字
Record all readings to the maximum precision of the instrument. For instance, a burette reading is taken to ±0.05 cm³ (reading to the nearest 0.05 cm³ by interpolating between 0.1 cm³ graduations). A thermometer graduated in 1 °C is read to ±0.5 °C.
记录读数时需达到仪器的最大精度。例如滴定管读数至 ±0.05 cm³（通过 0.1 cm³ 刻度间估读至 0.05 cm³）。分度值为 1 °C 的温度计读数至 ±0.5 °C。
Propagate uncertainties when combining measurements. For addition or subtraction, add absolute uncertainties. For multiplication or division, add percentage uncertainties. Always present your final result with the appropriate number of significant figures, typically matching the least precise measurement.
组合测量时需传递不确定度。加减运算，将绝对不确定度相加；乘除运算，将百分不确定度相加。最终结果的有效数字位数通常与最不精确的测量值一致。
For example, if you measure 25.0 cm³ (±0.5 cm³) of a solution with a measuring cylinder and calculate a concentration, the calculated concentration should reflect the 2% uncertainty from the volume measurement.
例如，用 25.0 cm³ (±0.5 cm³) 的量筒量取溶液并计算浓度，计算出的浓度应反映来自体积测量的 2% 不确定度。
3. Titration Technique and Calculation | 滴定技术与计算
Clean the burette with distilled water and then rinse with a small portion of the titrant. Fill the burette, remove the air from the jet, and record the initial volume. Use a pipette and pipette filler to transfer a known volume of the analyte into a conical flask, and add 2–3 drops of a suitable indicator.
用蒸馏水清洗滴定管，然后用少量滴定剂润洗。装入滴定剂，排去尖嘴中的空气，记录初始体积。用移液管和吸耳球量取已知体积的分析物置于锥形瓶中，加入 2–3 滴合适的指示剂。
Place a white tile under the flask to see the colour change clearly. Swirl the flask continuously while adding the titrant. Near the end point, add drop by drop, and finally fraction of a drop. The end point is reached when a permanent colour change occurs (e.g., phenolphthalein turns from colourless to the faintest pink that persists for 30 seconds).
在锥形瓶下垫白瓷板以便观察颜色变化。边摇动锥形瓶边滴加滴定剂。接近终点时，逐滴加入，最后可加入半滴。持续 30 秒的永久性颜色变化即为终点（例如酚酞由无色变为微粉色）。
Record the final burette reading. Repeat the titration until you obtain concordant titres (within 0.10 cm³ of each other). For an acid–base titration, use the equation moles = concentration × volume to find the unknown concentration. Remember that NaOH + HCl → NaCl + H₂O, so moles of acid = moles of alkali at the equivalence point.
记录滴定管的最终读数。重复滴定直至获得一致的滴定体积（彼此相差在 0.10 cm³ 以内）。对于酸碱滴定，使用公式 物质的量 = 浓度 × 体积 求出未知浓度。记住 NaOH + HCl → NaCl + H₂O，因此等当点时酸的物质的量等于碱的物质的量。
4. Preparation of a Standard Solution | 标准溶液的配制
Weigh the required mass of a primary standard (e.g., anhydrous sodium carbonate, Na₂CO₃) accurately on a balance. Transfer the solid into a beaker, dissolve in distilled water, and stir with a glass rod. Pour the solution through a funnel into a volumetric flask of appropriate volume.
用天平准确称量所需质量的基准物质（如无水碳酸钠 Na₂CO₃）。将固体转移至烧杯，用蒸馏水溶解并用玻璃棒搅拌。将溶液通过漏斗转移到合适体积的容量瓶中。
Rinse the beaker and the glass rod several times with distilled water and transfer the washings to the flask. Add distilled water until the meniscus reaches the graduation mark: use a dropping pipette for the last few drops. Stopper and invert the flask several times to ensure a homogeneous mixture.
用蒸馏水洗涤烧杯和玻璃棒数次，洗液一并转移到容量瓶中。加蒸馏水直至凹液面最低点与刻度线相切：最后几滴用滴管加。盖好瓶塞，倒转容量瓶数次以确保混合均匀。
The concentration (mol dm⁻³) is calculated from the mass of solute, the molar mass, and the final volume in dm³. Handle the primary standard carefully; it must be pure, stable in air, and have a high molar mass to minimise weighing errors.
浓度 (mol dm⁻³) 根据溶质质量、摩尔质量和最终体积 (dm³) 计算。小心操作基准物质；它必须纯净、在空气中稳定且具有较高的摩尔质量以减小称量误差。
5. Enthalpy Change Experiments | 焓变实验
Measure the enthalpy of neutralisation by adding a known volume of acid to a known volume of alkali in a polystyrene cup (a simple calorimeter). Record the initial temperatures of both solutions, mix quickly, stir, and record the maximum (or minimum) temperature reached.
测量中和焓变：在聚苯乙烯杯（简易量热计）中加入已知体积的酸和已知体积的碱。记录两种溶液的初始温度，快速混合，搅拌，记录达到的最高（或最低）温度。
Calculate the heat released or absorbed using q = m × c × ΔT, where m is the total mass of the solution (assuming density = 1 g cm⁻³), c is the specific heat capacity (typically 4.18 J g⁻¹ K⁻¹ for aqueous solutions), and ΔT is the temperature change. Then find the enthalpy change per mole of water formed or per mole of reactant.
使用 q = m × c × ΔT 计算放出或吸收的热量，其中 m 是溶液总质量（假设密度 = 1 g cm⁻³），c 是比热容（水溶液通常为 4.18 J g⁻¹ K⁻¹），ΔT 是温度变化。然后求出每摩尔生成水或每摩尔反应物的焓变。
For determination of an enthalpy of combustion, use a spirit burner to heat a known mass of water in a metal calorimeter. Weigh the burner before and after burning. Use the temperature rise of the water to estimate the energy released, and then scale to per mole of fuel. Account for heat losses by repeating and, where possible, plotting temperature against time to extrapolate the maximum theoretical temperature change.
测定燃烧焓时，用酒精灯加热金属量热计中已知质量的水。燃烧前后称量酒精灯的质量。利用水温上升估算释放的能量，然后换算成每摩尔燃料的焓变。考虑热损失，可重复实验并尽可能绘制温度–时间图，外推得到最大理论温度变化。
6. Investigating Reaction Rates | 反应速率探究
Monitor the rate of a reaction that produces a gas, such as the decomposition of hydrogen peroxide catalysed by manganese(IV) oxide: 2H₂O₂(aq) → 2H₂O(l) + O₂(g). Measure the volume of oxygen evolved at regular time intervals using a gas syringe or an inverted measuring cylinder filled with water.
监测产生气体的反应速率，例如过氧化氢在二氧化锰催化下的分解：2H₂O₂(aq) → 2H₂O(l) + O₂(g)。用气体注射器或倒置于水中的量筒，每隔一定时间记录产生的氧气体积。
Plot a graph of volume of gas against time. The initial rate is found from the gradient of the tangent at t = 0. To investigate the effect of concentration, repeat the experiment with different initial concentrations of H₂O₂ while keeping the volume, temperature, and catalyst mass constant.
绘制气体体积对时间的图。通过 t = 0 时切线的斜率求得初始速率。为探究浓度的影响，使用不同的 H₂O₂ 初始浓度重复实验，并保持总体积、温度和催化剂质量不变。
For a reaction that produces a colour change, such as the iodine clock reaction, time how long it takes for the colour to appear. The reciprocal of time (1/t) approximates the initial rate. Vary the concentration of one reactant while holding others constant to deduce the order of reaction.
对于产生颜色变化的反应，如碘钟反应，记录颜色出现所需的时间。时间的倒数 (1/t) 近似表示初始速率。改变一种反应物的浓度，保持其他条件不变，可推断反应级数。
7. Chromatography and Separation Techniques | 色谱法与分离技术
Use thin‑layer chromatography (TLC) or paper chromatography to separate components of a mixture. Draw a pencil baseline 1 cm from the bottom of the plate or paper. Spot the sample using a fine capillary tube, allowing each spot to dry between applications.
使用薄层色谱 (TLC) 或纸色谱分离混合物组分。用铅笔在薄层板或滤纸底部 1 cm 处画基线。用细毛细管点样，每次点样后晾干。
Place the plate in a jar containing a suitable solvent to a depth below the baseline. Cover the jar and allow the solvent to rise. Remove the plate when the solvent front is about 1 cm from the top, mark the solvent front with a pencil, and dry the plate.
将薄层板放入含有合适溶剂的展开缸中，溶剂深度低于基线。盖好缸盖，让溶剂上行。当溶剂前沿距顶端约 1 cm 时取出薄层板，用铅笔标记溶剂前沿，晾干。
Visualise spots under UV light or by staining (e.g., iodine vapour). Calculate Rf values (distance moved by spot ÷ distance moved by solvent front) and compare with literature values or authentic samples. For column chromatography, a slurry of silica gel is packed into a column, and the sample is eluted with a solvent or solvent gradient, collecting fractions.
在紫外光下或用显色剂（如碘蒸气）观察斑点。计算 Rf 值（斑点移动距离 ÷ 溶剂前沿移动距离），并与文献值或标准样对照。柱色谱中，将硅胶浆液填充到色谱柱中，用溶剂或溶剂梯度洗脱样品，收集馏分。
8. Electrochemical Cells and Electrolysis | 电化学电池与电解
Construct a simple galvanic cell by connecting two half‑cells (e.g., Zn²⁺/Zn and Cu²⁺/Cu) with a salt bridge (filter paper soaked in saturated KNO₃). Connect the metal electrodes through a voltmeter. Record the cell potential Ecell = Ecathode – Eanode.
构建简单的原电池：用盐桥（用饱和 KNO₃ 浸湿的滤纸）连接两个半电池（如 Zn²⁺/Zn 和 Cu²⁺/Cu）。用电压表连接金属电极。记录电池电势 Ecell = E阴极 – E阳极。
In electrolysis experiments, use inert electrodes (graphite or platinum) to electrolyse aqueous solutions such as copper(II) sulfate or sodium chloride. Observe which products form at the anode and cathode; use a glowing splint to test for O₂ and a burning splint for H₂. For halide solutions, use damp blue litmus paper (or starch‑iodide paper) at the anode to detect chlorine.
在电解实验中，使用惰性电极（石墨或铂）电解硫酸铜(II)或氯化钠等水溶液。观察阳极和阴极生成的产物；用带火星的木条检验 O₂，用点燃的木条检验 H₂。对于卤化物溶液，在阳极用湿润的蓝色石蕊试纸（或淀粉碘化钾试纸）检测氯气。
Quantitative electrolysis can determine the Avogadro constant or Faraday constant. Measure the current, time, and mass of metal deposited at the cathode. Use charge Q = I × t and moles of electrons = Q / (96500 C mol⁻¹), relating the moles of metal deposited to the moles of electrons via the half‑equation.
定量电解可用于测定阿伏伽德罗常数或法拉第常数。测量电流、时间以及阴极析出的金属质量。利用电荷量 Q = I × t 和电子物质的量 = Q / (96500 C mol⁻¹)，通过半反应式将析出的金属物质的量与电子物质的量关联起来。
9. Qualitative Analysis – Inorganic Ions | 定性分析 – 无机离子
Carry out flame tests to identify metal cations. Clean a nichrome wire loop with concentrated HCl and hold in a blue Bunsen flame until no colour is seen. Dip the loop in the sample and hold in the flame: Li⁺ gives a red flame, Na⁺ gives a persistent yellow, K⁺ gives lilac, Ca²⁺ gives brick‑red, and Ba²⁺ gives apple‑green.
进行焰色反应鉴定金属阳离子。用浓盐酸清洗镍铬丝环，在蓝色本生焰中灼烧至无色。将环浸入样品中，再置于火焰中：Li⁺ 呈红色，Na⁺ 呈持久黄色，K⁺ 呈淡紫色，Ca²⁺ 呈砖红色，Ba²⁺ 呈苹果绿。
Test for anions: add dilute nitric acid followed by silver nitrate solution to detect halide ions. Cl⁻ gives a white precipitate (soluble in dilute ammonia), Br⁻ gives a cream precipitate (soluble in concentrated ammonia), I⁻ gives a yellow precipitate (insoluble in ammonia). To test for carbonate, add dilute acid and look for effervescence; pass the gas through limewater to check for CO₂ (turns milky).
阴离子鉴定：加入稀硝酸后再加硝酸银溶液可检验卤离子。Cl⁻ 产生白色沉淀（溶于稀氨水），Br⁻ 产生奶油色沉淀（溶于浓氨水），I⁻ 产生黄色沉淀（不溶于氨水）。检验碳酸根时，加入稀酸观察是否有气泡；将气体通入石灰水检查 CO₂（变浑浊）。
For sulfate ions, add dilute hydrochloric acid and then barium chloride solution; a white precipitate of BaSO₄ confirms sulfate. For ammonium ions, warm the sample with sodium hydroxide solution; ammonia gas is given off, detected by its characteristic odour or by turning damp red litmus paper blue.
检验硫酸根离子时，加入稀盐酸再加入氯化钡溶液；白色沉淀 BaSO₄ 可确认硫酸根。检验铵根离子时，将样品与氢氧化钠溶液温热；产生的氨气可通过其特征气味或用湿润的红色石蕊试纸变蓝来检验。
10. Graduated Apparatus and Accurate Measurement | 精密玻璃量具与准确测量
Select the correct apparatus for the task: a volumetric flask for making standard solutions, a burette for dispensing variable volumes accurately (titration), a pipette for fixed volumes, and a measuring cylinder for approximate volumes. Always read the bottom of the meniscus at eye level to avoid parallax error.
根据任务选择正确的仪器：容量瓶用于配制标准溶液，滴定管用于准确加入可变体积（滴定），移液管量取固定体积，量筒用于近似体积。始终在视线水平处读取凹液面最低点以避免视差。
When using a balance, tare an empty container before weighing. Record the mass to the balance’s maximum decimal places (e.g., 0.001 g for an analytical balance). For reactions sensitive to atmospheric moisture or CO₂, use a fresh sample and work quickly.
使用天平时，称量前先对空容器去皮。记录质量至天平的最大小数位（如分析天平至 0.001 g）。对于对空气中水分或 CO₂ 敏感的反应，使用新样品并快速操作。
Temperature can affect volumes, so use solutions that have been equilibrated to room temperature. In calorimetry, correct for the heat capacity of the apparatus by calibration or perform a dummy run with the same temperature change to determine the apparatus correction.
温度会影响体积，因此使用已平衡至室温的溶液。在量热实验中，可通过校准来校正仪器的热容，或进行一个温度变化相同的空白实验以确定仪器修正值。
11. Synthesis and Purification of an Organic Solid | 有机固体的合成与提纯
A typical synthesis is aspirin from salicylic acid and ethanoic anhydride. Reflux the mixture, then cool to induce crystallisation. Use suction filtration (Büchner funnel) to collect the crude product. Wash with cold solvent to remove impurities.
阿司匹林的合成是一个典型实验：用水杨酸和乙酸酐回流反应，然后冷却使其结晶。用抽滤（布氏漏斗）收集粗产物。用冷溶剂洗涤以除去杂质。
Purify by recrystallisation. Dissolve the crude solid in the minimum volume of hot solvent, filter while hot to remove insoluble impurities, then allow the filtrate to cool slowly. Collect the pure crystals, wash with a little cold solvent, and dry between filter papers or in a desiccator.
通过重结晶提纯。将粗产物溶于最小量热溶剂中，趁热过滤除去不溶性杂质，然后让滤液缓慢冷却。收集纯结晶，用少量冷溶剂洗涤，在滤纸之间压干或置于干燥器中干燥。
Check purity by determining the melting point. A pure substance has a sharp melting point (range ≤ 2 °C) that matches the literature value. Impurities lower and broaden the melting range. Compare with the literature value and, if available, a mixed melting point with an authentic sample to confirm identity.
用熔点检测纯度。纯净物质具有尖锐的熔点（熔程 ≤ 2 °C），且与文献值一致。杂质会降低熔点并使熔程变宽。对照文献值，如果条件允许，与标准样做混合熔点测定以确认。
12. Data Processing, Graphs, and Error Analysis | 数据处理、作图与误差分析
Present raw data in clearly labelled tables with units in the header. Process data stepwise, showing one sample calculation for each formula used. Use graphs wherever a relationship is investigated: plot the independent variable on the x-axis and the dependent variable on the y-axis, label axes with quantity and unit, and choose scales that spread data over more than half the graph.
将原始数据呈现在清晰标注的表格中，表头注明单位。分步处理数据，对每个使用的公式给出一个示例计算。研究关系时尽量作图：自变量放在 x 轴，因变量放在 y 轴，坐标轴标注量和单位，选择使数据点占据图形一半以上的标度。
Draw a line of best fit – a straight line if the relationship is linear, or a smooth curve. Calculate the gradient using a large triangle, not data points. Uncertainty in measurements can be shown as error bars. Discuss the percentage error and identify the largest source of uncertainty; suggest realistic improvements.
绘制最佳拟合线——如果是线性关系画直线，否则画平滑曲线。用大的直角三角形计算斜率，而非直接用数据点。测量不确定度可用误差棒表示。讨论百分误差并识别最大的不确定度来源；提出切实可行的改进建议。
When drawing conclusions, refer to the graph’s trend and numerical comparisons. For example, state ‘the volume of gas increases linearly with time during the first 120 seconds, indicating a constant rate,’ and then quantify the rate with its units. Critically evaluate the experiment: were there systematic errors (e.g., heat loss) or random errors (e.g., inconsistent swirling)?
得出结论时，要引用图形的趋势和数值比较。例如表述 ‘气体体积在前 120 秒内随时间线性增加，表明速率恒定’，然后量化速率并给出单位。批判性地评价实验：存在系统误差（如热损失）还是随机误差（如摇动不一致）？
Published by TutorHao | Chemistry Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
屏轩国际教育cambridge primary/secondary checkpoint, cat4, ukiset,ukcat,igcse,alevel,PAT,STEP,MAT, ibdp,ap,ssat,sat,sat2课程辅导，国外大学本科硕士研究生博士课程论文辅导