Report 1: Acid-Base Titration
报告 1：酸碱滴定

Please leave Report Feedback blank, your tutor will use this area to give you feedback.
请将 Report Feedback （报告反馈） 留空，您的导师将使用此区域为您提供反馈。

COURSEWORK SUBMISSION FORM
课程作业提交表

TO THE STUDENT: Please complete the boxes, and submit one electric copy per group to the corresponding moodle submission box.
给学生：请填写盒子，并将每组一份电子副本提交到相应的 Moodle 提交箱。

ABSTRACT:
摘要：

The abstract should be a single paragraph and summarise the overall report. The Abstract should include:
摘要应为单个段落，并总结整个报告。摘要应包括：

A statement of the hypothesis being tested in this experiment.
本实验中正在检验的假设的陈述。

A brief explanation of how the hypothesis was tested.
对假设的简要解释进行了检验。

A summary of the conclusion of the report quantitively (including individual data agreement, relevant coefficients/determinates, main errors, etc.)
报告结论的定量摘要（包括个人数据一致性、相关系数/确定、主要误差等）。）

You should also refer to “Video 2 - Abstract” in the “Report Writing” section of Moodle for to help you complete this section.
您还应该参考 Moodle 的“报告写作”部分中的“视频 2 - 摘要”，以帮助您完成本节。

The hypothesis tested was that the concentration of an unknown sodium hydroxide (NaOH) solution could be accurately determined through acid-base titration with a standardised sulfuric acid () solution. The hypothesis was tested by titrating a known volume of 0.1 M against the NaOH solution, using phenolphthalein as an indicator. The endpoint was determined by the colour change of the indicator from colourless to pink. The results showed that the measured concentration of the NaOH solution was [calculated molarity] M. The individual titre volumes varied with values of 12.30 mL, 11.55 mL, 12.40 mL and 11.40 mL for analyses 1 - 4 respectively. Average volume of titter was used to calculate concentration. The primary errors observed were due to possible inaccuracies in the burette readings, a drop of sodium hydroxide sticking to the wall of a conical flask, the phenolphthalein reagent not starting to change colour until the pH was 10.0, and the approximation of the end point with the indicator. The experimental results did not fully agree with the predicted concentration of 0.2 M, indicating that the hypothesis was not fully supported.
检验的假设是，可以通过使用标准化硫酸 （ ） 溶液进行酸碱滴定来准确测定未知氢氧化钠 （NaOH） 溶液的浓度。 使用酚酞作为指示剂，通过对 NaOH 溶液滴定已知体积的 0.1 M 来检验该假设。终点由指示剂的颜色从无色变为粉红色确定。结果表明，NaOH 溶液的测量浓度为 [计算摩尔浓度] M。对于分析 1 - 4，单个滴度体积的值分别为 12.30 mL、11.55 mL、12.40 mL 和 11.40 mL。使用平均滴定体积计算浓度。观察到的主要误差是由于滴定管读数可能不准确、一滴氢氧化钠粘在锥形瓶壁上、酚酞试剂在 pH 值为 10.0 之前才开始变色，以及终点与指示剂的近似值。实验结果与预测浓度 0.2 M 不完全一致，表明该假设不完全支持。

Health & Safety Information
健康与安全信息

The Health and Safety information includes a table identifying the Health and Safety information relating to the chemical used in this experiment. Use the “Risk Assessment -Lab 1.1 MSDS” and the “Health & Safety – Presentation” to help you complete this section.
健康和安全信息包括一个表格，用于标识与本实验中使用的化学品相关的健康和安全信息。使用“风险评估 - 实验室1.1 MSDS”和“健康与安全 - 演示”来帮助您 完成此部分。

Complete the following table, with all the chemicals used in this experiment.
完成下表，包括本实验中使用的所有化学品。

Table 1a: Health and Safety Assessment of the Chemicals used for the Experiment.
表 1a：用于实验的化学品的健康和安全评估。

Chemical Name 化学名称	Hazard Pictogram(s) 危险象形图	Hazard Phrases 危险短语
Sulfuric acid 硫酸		Danger D愤怒 H290 May be corrosive to metals. H290 可能对金属有腐蚀性。 H314 Causes severe skin burns and eye damage. H314 导致严重的皮肤灼伤和眼睛损伤。
Sodium hydroxide solution 氢氧化钠溶液	Not a hazardous substance or mixture according to Regulation (EC) No. 1272/2008. This substance is not classified as dangerous according to Directive 67/548/EEC. 不是第 1272/2008 号法规 （EC） 规定的有害物质或混合物。根据指令 67/548/EEC，该物质未被归类为危险物质。	None 没有
Phenolphthalein solution 酚酞溶液		Danger D愤怒 H225 Highly flammable liquid and vapour. H225 高度易燃的液体和蒸气。 H319 Causes serious eye irritation. H319 引起严重的眼睛刺激。

OBJECTIVES OF THE EXPERIMENT:
实验目标：

State the objective(s) of the experiment, these can be found on the instruction sheet for each experiment.
说明实验的目标，这些可以在每个实验的说明书上找到。

You should also refer to “Video 3 - Objectives & Introduction and Assumptions” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告写作”部分的“视频3 - 目标&介绍和假设”以帮助您完成此部分。

The primary objective of this experiment was to accurately determine the concentration of a sodium hydroxide solution through acid - base titration techniques. Additionally, it aimed to enhance practical skills in using titration equipment and understanding the principles of acid - base reactions
本实验的主要目的是通过酸碱滴定技术准确测定氢氧化钠溶液的浓度。此外，它还旨在提高使用滴定设备和了解酸碱反应原理的实践技能.

INTRODUCTION:
简介：

Lectures 9 & 10 are relevant to this practical experiment and report, which you can find the slides in the section “Additional help with the content of the report”. You should use these lectures as reference material, in addition to the recommended text book.
第9和10讲与这个实际实验和报告有关，你可以在“报告内容的额外帮助”部分找到幻灯片。 除了推荐的教科书外，您还应该将这些讲座用作参考资料。

The Introduction section could include;
Introduction 部分可能包括;

What is the difference between an acid and a base (talk about the different theories of acids and bases)?
酸和碱有什么区别（谈谈酸和碱的不同理论）？

What is the difference between a strong acid versus a weak acid?
强酸和弱酸有什么区别？

What does the term percent ionisation mean?
电离百分比是什么意思？

When measuring the hydronium ion, [H⁺], concentration of a solution, why do we use a pH scale?
在测量水合氢离子 [H⁺] 溶液浓度时，为什么使用 pH 值？

If a solution has a pH of 2, and another solution has a pH of 4, what does this mean? How many times more acidic is the first solution?
如果一种溶液的 pH 值为 2，而另一种溶液的 pH 值为 4，这是什么意思？第一种溶液的酸性是多少倍？

Explain the term K_a & K_b, and explain what a value for each of these constants can tell us.
解释术语 K_a & K_b，并解释这些常数的值可以告诉我们什么。

Explain the principles involved in carrying out a titration. In particular, explain the term ‘equivalence point’.
解释 进行滴定所涉及的原则。特别是，解释术语“等当点”。

A statement of the hypothesis being tested.
正在检验的假设的陈述。

Additional marks will be given for additional scientifically relevant information.
对于额外的科学相关信息，将给予额外的分数。

You should also refer to “Video 3 - Objectives & Introduction and Assumptions” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告写作”部分的“视频3 - 目标&介绍和假设”以帮助您完成此部分。

Acids and bases are defined through three main theories. Arrhenius theory (1884) states acids release H⁺ ions and bases release OH⁻ ions in water, but it is limited to aqueous solutions. Brønsted-Lowry theory (1923) generalizes acids as proton donors (e.g., HCl donating H⁺) and bases as proton acceptors (e.g., NH₃ accepting H⁺), explaining reactions in non-aqueous media. Lewis’s theory (1923) broadens the definition: acids accept electron pairs while bases donate electron pairs, encompassing reactions without protons.
酸和碱通过三个主要理论定义。Arrhenius 理论 （1884） 指出酸在水中释放 H⁺ 离子，碱释放 OH⁻ 离子，但仅限于水溶液。Brønsted-Lowry 理论 （1923） 将酸推广为质子供体（例如，HCl 提供 H⁺），将碱推广为质子受体（例如，NH₃ 接受 H⁺），解释了非水介质中的反应。刘易斯理论（1923 年）拓宽了定义：酸接受电子对，而碱提供电子对，包括没有质子的反应。

A strong acid completely dissociates in an aqueous solution, while a weak acid only partially dissociates.
强酸在水溶液中完全解离，而弱酸仅部分解离。

Percent ionization quantifies the extent to which a weak acid or base dissociates in solution, expressed as the ratio of ionized species to the initial concentration, multiplied by 100. For a weak acid (HA → H⁺ + A⁻), it is calculated as [H⁺] / [HA]_initial × 100%, reflecting the compound’s strength. Higher percent ionization indicates greater dissociation. This value is inversely related to concentration—dilute solutions exhibit higher ionization—and is temperature-dependent.
电离百分比量化了弱酸或弱碱在溶液中解离的程度，表示为电离物质与初始浓度的比值乘以 100。对于弱酸 （HA → H⁺ + A⁻），计算公式为 [H⁺] / [HA]_initial × 100%，反映了化合物的强度。电离百分比越高，解离程度越高。该值与浓度成反比（稀溶液表现出更高的电离度），并且与温度有关。

The pH scale simplifies expressing hydronium ion concentration ([H₃O⁺] or [H⁺]) because it compresses a wide range of values (e.g., 10⁻¹ to 10⁻¹⁴ M) into a manageable 0–14 scale. Mathematically, pH = −log[H⁺] converts exponential concentrations into linear values for easier comparison and interpretation. For example, a tenfold difference in [H⁺] corresponds to a one-unit pH change. This logarithmic scale avoids cumbersome notation (e.g., pH 2 instead of 0.01 M H⁺)
pH 标尺简化了水合氢离子浓度（[H₃O⁺] 或 [H⁺]）的表示，因为它将广泛的值（例如，10⁻¹ 至 10⁻¹⁴ M）压缩成一个可管理的 0-14 标度。在数学上，pH = −log[H⁺] 将指数浓度转换为线性值，以便于比较和解释。例如，[H⁺] 的 10 倍差异对应于1 个单位的 pH 值变化。此对数刻度避免了繁琐的符号（例如，pH 2 而不是 0.01 M H⁺）

A solution with pH 2 has a higher hydronium ion concentration ([H⁺]) than one with pH 4. Since pH = −log[H⁺], a difference of 2 pH units corresponds to a 10² = 100-fold difference in acidity. Specifically: pH 2 → [H⁺] = 10⁻² M, pH 4 → [H⁺] = 10⁻⁴ M The first solution is 100 times more acidic because 10⁻² / 10⁻⁴ = 100. This logarithmic relationship highlights how small pH changes reflect large differences in acidity.
pH 值为 2 的溶液比 pH 值为 4 的溶液具有更高的水合氢离子浓度 （[H⁺]）。由于 pH = −log[H⁺]，因此 2 个 pH 单位的差异对应于 10² = 100 倍的酸度差异。具体来说： pH 2 → [H⁺] = 10⁻² M，pH 4 → [H⁺] = 10⁻⁴ M第一种溶液的 酸性是 100 倍，因为 10⁻² / 10⁻⁴ = 100。这种对数关系突出了微小的 pH 值变化如何反映酸度的巨大差异。

is the acid dissociation constant, which measures the extent of acid dissociation. A larger value indicates a stronger acid. is the base dissociation constant, and a larger value indicates a stronger base.
是酸解离常数，用于测量酸解离的程度。值越大 表示酸度越高。 是碱基解离常数，值越大 表示碱基越强。

Titration is a technique used to determine the concentration of an unknown solution by reacting it with a known - concentration solution. The equivalence point is the point at which the moles of acid equal the moles of base in a chemical reaction.
滴定是一种通过与已知浓度溶液反应来确定未知溶液浓度的技术。等当点是化学反应中酸的摩尔数等于碱的摩尔数的点。

In this experiment, the hypothesis was that the concentration of the NaOH solution could be accurately determined by titrating it with a standardized solution.
在这个实验中，假设是可以通过用标准化溶液滴定来准确确定 NaOH 溶液的浓度 。

ASSUMPTIONS:
假设：

The assumptions section should take the form of a bullet point list of the major assumptions of this experiment (It is recommended to write as much as the number of marks allocated for assumptions and do not forget the key assumptions.)
假设部分应采用本实验主要假设的要点列表的形式（建议写下与分配给假设的分数一样多，并且不要忘记关键假设s。）

You should also refer to “Video 3 - Objectives & Introduction and Assumptions” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告写作”部分的“视频3 - 目标&介绍和假设”以帮助您完成此部分。

APPARATUS
装置

The apparatus section should take the form of a bullet point list, stating all of the equipment/resources that were used to perform the experiment.
设备部分应采用项目符号列表的形式，说明用于执行实验的所有设备/资源。

You should also refer to “Video 4 - Apparatus & Procedure” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告撰写”部分的“视频4 - 仪器与程序”以帮助您完成此部分。

PROCEDURES
程序S

The procedures should state what was done during the experiment in sufficient detail that another scientist who has not seen the experiment could understand what you have done and could repeat the experiment themselves. The procedure should be written in paragraphs, NOT as a list or bullet points.
该程序应足够 详细地说明实验期间做了什么，以便其他没有看过实验的科学家可以理解您做了什么，并且可以自己重复实验。 该程序应该以段落的形式编写，而不是以列表或项目符号的形式编写。

A good tip for writing the procedure is to paraphrase the key points of the instruction from the lab worksheet in the past passive voice.
编写程序的一个很好的技巧是用过去的被动语态解释实验工作表中指令的关键点。

You should also refer to “Video 4 - Apparatus & Procedure” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告撰写”部分的“视频4 - 仪器和程序”以帮助您完成此部分。

RESULTS:
结果：

The results section should show the data from the experiment as well as any graphs you have made to analyse this data. This section should also include some sample calculations to show how you worked out various quantities.
结果部分应显示实验数据以及您为分析这些数据而制作的任何图表。本节还应包括一些示例计算，以展示您如何计算各种数量。

The results section should include (in order)
结果部分应包括 （按顺序）

A sample calculation showing how you worked out titre volume_, for measurement 1. This should include a brief explanation of what you are calculating and what equation you are using.
显示如何计算测量 1 的滴度体积的示例计算。 这应该包括对您正在计算的内容以及您正在使用的方程式的简要说明。

A sample calculation showing how you worked out the molarity of NaOH solution.
显示如何计算 NaOH 溶液摩尔浓度的示例计算。

Completion of Table 2 & 3 with your results.
完成表2和表3以及你的结果。

Consider whether you should include your initial/rough analysis in the calculation. Explain why you have made that particular decision.
考虑是否应在计算中包括初始/粗略分析。解释您为什么做出这个特定的决定。

You should also refer to “Video 5 - Results & Uncertainty Analysis” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告写作”部分的“视频5 - 结果与不确定性分析”以帮助您完成此部分。

Table 2. Titration observations and calculations
表 2. 滴定观察和计算

Table 3: Titration Results
表 3：滴定结果

Using the titre volumes in the above table, determine the measured concentration of the sodium hydroxide solution (Molarity)
使用上表中的滴定度，确定氢氧化钠溶液的测量浓度（摩尔浓度）

UNCERTAINTY ANALYSIS:
UNCERTAINTY ANALYSIS：

As described in the Scientific Method module (CELEN038), you can do this in a number of different approaches. Examples are
如科学方法模块 （CELEN038） 中所述，您可以使用多种不同的方法执行此作。例如：

Calculating the mean and standard uncertainty of your replicate measurements;
计算重复测量的均值和标准不确定度;

Or
或者

Propagation of errors for each of the variables (such as uncertainty for burette reading , uncertainty for the calculated titre volume , uncertainty in average titre volume and )
每个变量的误差 P 排序（例如滴定管读数 的不确定性、计算滴度体积 的不确定性、平均滴度体积的不确定性和 ）

Using either of these approaches, calculate (showing your calculations) the uncertainty associated with your average sodium hydroxide concentration, as calculated below Table 2
使用这些方法中的任何一种，计算（显示您的计算结果）与平均氢氧化钠浓度相关的不确定性，如表 2 所示

You should also refer to “Video 5 - Results & Uncertainty Analysis” in the “Report Writing” section of Moodle for to help you complete this section.
您也应该参考Moodle的“报告写作”部分的“视频5 - 结果与不确定性分析”以帮助您完成此部分。

DISCUSSION:
讨论：

The discussion section of the report is where you discuss the results of the experiment. It is here you can demonstrate that you understand what the data is telling you by comparing your measured (actual) results with the predicted results.
报告的讨论部分是您讨论实验结果的地方。在这里，您可以通过将测量的 （实际） 结果与预测结果进行比较来证明您了解数据所告诉您的内容。

The discussion is generally split into 3 paragraphs;
讨论通常分为 3段;

In the first we compare the measured and predicted results;
首先，我们比较测量结果和预测结果;

Next we look for any patterns in the data and discuss possible reasons why the measured values may differ from the predicted values.
接下来，我们在数据中查找任何模式，并讨论 测量值可能与预测值不同的可能原因。

Use the following questions to help you write your discussion (Do not just answer the questions: form your responses into coherent sentences & paragraphs):
你选择以下问题来帮助你写你的讨论（不仅仅是回答问题：把你的回答整理成连贯的句子和段落）：

Paragraph 1:
第 1 段：

How many of your individual titration results agree with the predicted value?
您的单个滴定结果中有多少与预测值一致？

Overall, do the results support your hypothesis, that your results agree with the predicted sodium hydroxide concentration or not?
总的来说，结果是否支持您的假设，即您的结果是否与预测的氢氧化钠浓度一致？

Paragraph 2:
第 2 段：

For any of your results which that differed from your predicted results (outside of the uncertainty range), what are the possible sources of these discrepancies? Hint: consider your assumptions.
对于与 预测结果不同的任何结果（超出不确定性范围），这些差异的可能来源是什么？ Hint：考虑您的假设。

Are there any observable patterns in your data, which might explain any trends in your results.
您的数据中是否有任何可观察的模式，这些模式可以解释结果中的任何趋势。

Paragraph 3:
第 3 段：

What did you observe happen to the colour of the phenolphthalein as you added the base to the acid? Why do you think you observed this?
当您将碱添加到酸中时，您观察到酚酞的颜色发生了什么变化？你觉得你为什么观察到这个？

Show the calculation to determine the pH in the flask after added 8 ml of base was added.
显示计算结果以确定加入 8 ml 碱后培养瓶中的 pH 值。

N.B. It is not enough to say yes or no! As discussed in the Scientific Method module, your answer must be supported by referring to data from the Results section.
注意：仅仅说是或不是是不够的！正如科学方法模块中所讨论的，您的答案必须 得到 Results 部分中数据的 引用支持。

You should also refer to “Video 6 - Discussion” in the “Report Writing” section of Moodle for to help you complete this section.
您还应该参考 Moodle 的“报告写作”部分中的“视频 6 - 讨论”，以帮助您完成本节。

CONCLUSION:
结论：

The conclusion section is where you come to a final decision regarding whether or not the experiment supports the hypothesis or not. It should be split into two paragraphs as shown below.
结论部分是您就实验是否支持假设或不支持 t 做出最终决定的地方。它应该分成两个段落，如下所示。

Use the following questions to help you write your conclusion (do not just answer the questions: form your responses into coherent sentences & paragraphs):
你选择以下问题来帮助你写出你的结论（不仅仅是回答问题：把你的回答整理成连贯的句子和段落）：

Paragraph 1
第 1 段

What was the initial hypothesis for the experiment?
实验的最初假设是什么？

Based on what you have said in the discussion section, does your experiment demonstrate the validity of your hypothesis or not?
根据你在讨论部分所说的，你的实验是否证明了你的假设的有效性？

Paragraph 2
第 2 段

Which of the factors from the discussion section is the main source of any measured results differing from predicted results?
讨论部分的哪些因素是任何测量结果与预测结果不同的主要来源？

What improved experimental techniques or mathematical models could account for these discrepancies in future investigations?
哪些改进的实验技术或数学模型可以解释未来调查中的这些差异？

N.B. It is not enough to say yes or no! As discussed in the Scientific Method module, your answer must be supported by referring to data from the Results/Discussion sections.
注意：仅仅说是或不是是不够的！正如科学方法模块中所讨论的，您的答案必须得到 Results/Discussion 部分s 中数据的 参考支持。

You should also refer to “Video 7 - Conclusion” in the “Report Writing” section of Moodle for to help you complete this section.
你亦应参阅 Moodle 的 “报告撰写” 部分的 “影片 7 - 结论” ，以帮助你完成这部分。