Key Points for Experimental and Practical Assessments in Year 7 CCEA Science | Year 7 CCEA 科学：实验/实践考核要点

📚 Key Points for Experimental and Practical Assessments in Year 7 CCEA Science | Year 7 CCEA 科学：实验/实践考核要点

Practical work is at the heart of Year 7 CCEA Science. It helps you develop essential skills such as observing, measuring, recording and drawing conclusions. In your assessments, you will be tested not only on what you know but also on how well you can plan, carry out and evaluate a simple investigation.

实践操作是 Year 7 CCEA 科学课程的核心。它能帮助你培养观察、测量、记录和得出结论等关键技能。在考核中，不仅会考查你学到的知识，还会考查你计划、实施和评估一个简单探究实验的能力。

1. Safety First | 安全第一

Always wear safety goggles when handling chemicals, heating substances or using glassware under pressure. You must never remove your goggles during an experiment unless your teacher tells you it is safe to do so.

在处理化学品、加热物质或使用承受压力的玻璃器皿时，务必佩戴护目镜。除非老师明确表示可以，否则在实验过程中绝不能摘下护目镜。

Tie back long hair, tuck in ties and remove any dangling jewellery when working near a Bunsen burner or open flame. Loose items can catch fire or get caught in equipment.

靠近本生灯或明火操作时，要把长发束起、塞好领带，并摘下任何悬挂的饰品。宽松的物品可能会着火或被设备钩住。

Know the location of the fire extinguisher, fire blanket and first aid kit, and how to report an accident immediately. In an assessment, showing awareness of emergency procedures earns credit for safe planning.

要清楚灭火器、灭火毯和急救箱的位置，并知道如何立即报告事故。在考核中，表现出对应急程序的了解会让你的安全计划得分。

Never taste any chemical, and always waft fumes towards your nose with your hand instead of sniffing directly from a test tube. Wash your hands after every practical session.

绝对不要品尝任何化学品，闻气味时要用手将气体扇向鼻子，而不是直接把试管凑到鼻子前。每次实验课结束后都要洗手。

2. Apparatus and Equipment | 仪器与设备

You are expected to recognise and correctly name common laboratory apparatus, including beaker, conical flask, measuring cylinder, test tube, funnel, evaporating dish, tripod and gauze, thermometer and stopwatch.

你需要认识并能正确说出常见的实验室仪器名称，包括烧杯、锥形瓶、量筒、试管、漏斗、蒸发皿、三脚架和石棉网、温度计以及秒表。

Apparatus 仪器	Common use 常见用途
Measuring cylinder 量筒	Measures volume of liquids accurately 精确测量液体体积
Thermometer 温度计	Measures temperature in degrees Celsius (°C) 测量温度，单位为摄氏度
Bunsen burner 本生灯	Provides a clean, hot flame for heating 提供洁净高温火焰用于加热
Electronic balance 电子天平	Measures mass in grams (g) or kilograms (kg) 测量质量，单位为克或千克

For each piece of equipment, you should be able to explain why it is chosen over another. For example, a measuring cylinder gives more precise volume readings than a beaker, and a thermometer is the correct tool for checking temperature changes, not your finger.

针对每一件仪器，你应该能解释为什么选择它而不是其他。例如，量筒比烧杯提供更精确的体积读数，而温度计是检查温度变化的正确工具，而不是你的手指。

3. Making Measurements | 进行测量

When reading the volume of a liquid in a measuring cylinder, always read the bottom of the curved surface (the meniscus) at eye level. This avoids parallax error and gives the true volume.

读取量筒中液体的体积时，始终在视线水平的高度读取弯曲液面（凹液面）的最低点。这能避免视差错误，得到真实的体积。

Record all measurements with the correct unit. Common units in Year 7 include centimetres (cm), metres (m), grams (g), kilograms (kg), seconds (s), degrees Celsius (°C) and cubic centimetres (cm³). Leaving out the unit can lose marks in an assessment.

记录所有测量结果时都要带上正确的单位。Year 7 常用的单位包括厘米、米、克、千克、秒、摄氏度以及立方厘米。漏写单位会在考核中丢分。

Use the most suitable instrument for the measurement you need. For instance, use a thermometer to measure temperature, a stopwatch for time, a ruler or measuring tape for length, and an electronic balance for mass. Know how to zero the balance before use.

根据你要进行的测量选择最合适的仪器。例如，使用温度计测量温度，用秒表计时，用直尺或卷尺测量长度，用电子天平测量质量。要学会使用前将天平归零。

Repeat your measurements when possible and calculate the mean (average) to improve reliability. In an assessment, you should suggest repeating readings if an anomalous result is spotted.

可能的话应重复测量并计算平均值以提高可靠性。在考核中，如果发现异常数据，你应该建议重复读数。

4. Making Observations | 进行观察

Observation involves using all your senses safely, but especially sight. Common observations include changes in colour, formation of bubbles (gas given off), formation of a solid (precipitate), temperature change and a change in smell.

观察包括在安全前提下运用所有感官，尤其重要的是视觉。常见的观察包括颜色变化、气泡生成（放出气体）、固体生成（沉淀）、温度变化以及气味变化。

Describe observations using precise language, not vague terms. Instead of writing ‘it fizzed a lot’, write ‘rapid effervescence was observed and a colourless gas was produced’. Quantitative descriptions, such as ‘the temperature rose by 12°C’, are highly valued.

用准确的语言描述观察结果，不要用模糊的措辞。比如，不要写“它冒了很多泡”，而应写“观察到快速起泡现象，同时生成了一种无色气体”。定量描述如“温度上升了 12 °C”非常受重视。

Record observations immediately during the experiment, not from memory afterwards. Use a results table to log time and the corresponding observation or measurement, so you do not miss any detail.

在实验过程中要立即记录观察结果，而不是事后凭记忆记录。使用结果表格记录时间和相应的观察或测量数据，这样就不会遗漏任何细节。

5. Fair Testing and Variables | 公平测试与变量

In any investigation, you need to identify three types of variables: independent (the one you change), dependent (the one you measure) and control (the ones you keep the same to make the test fair).

在任何探究实验中，你需要识别三种变量：自变量（你改变的变量）、因变量（你测量的变量）以及控制变量（你保持不变的变量，以使测试公平）。

For example, when investigating how water temperature affects the time it takes for sugar to dissolve, the independent variable is water temperature, the dependent variable is dissolving time, and control variables include the mass of sugar, volume of water and stirring rate.

例如，在探究水温如何影响砂糖溶解时间时，自变量是水温，因变量是溶解时间，控制变量包括砂糖的质量、水的体积和搅拌速度。

When writing a method for an assessment, explicitly state which variables you will control and how. This shows understanding of fair testing, which is a key criterion in CCEA practical mark schemes.

在考核中撰写实验方法时，要明确说明你将控制哪些变量以及如何控制。这展示了你对公平测试的理解，这是 CCEA 实践评分方案的一个关键标准。

6. Recording Results | 记录结果

All results must be written in a neatly ruled table before any graph is drawn. Each column heading must include both the quantity and its unit, such as ‘Time (s)’ or ‘Temperature (°C)’. Never put units inside the body of the table.

绘制任何图表之前，所有结果都必须记录在整洁的画线表格中。每一栏的表头必须同时包含物理量和单位，例如“时间 (s)”或“温度 (°C)”。千万不要把单位写在表格数据的格子内。

Enter data consistently to the same number of decimal places based on the precision of your measuring instrument. A thermometer reading to 1°C should be recorded as 23°C, not 23.0°C, whereas an electronic balance measuring to 0.1 g might give 5.0 g.

根据测量仪器的精度，始终将数据记录到相同的小数位数。精度为 1°C 的温度计读数应记录为 23°C，而非 23.0°C；而精度为 0.1 g 的电子天平读数可能记为 5.0 g。

If you spot a result that does not fit the pattern (an anomaly), circle it in your table but do not rub it out. In the evaluation section, you can suggest a reason for the anomaly and state that repeating it would improve reliability.

如果发现某个结果不符合整体规律（异常值），请在表格中将其圈出来，但不要擦掉。在评估部分，你可以解释产生异常值的原因，并说明重复该测量会提高可靠性。

7. Presenting Data in Graphs | 用图表展示数据

Choose the correct type of graph for your data. In Year 7 CCEA Science, you will mainly use bar charts for categoric data (e.g. colours, types of material) and line graphs for continuous data (e.g. temperature over time).

根据数据类型选择合适的图表。在 Year 7 CCEA 科学中，你主要使用条形图来表示分类数据（如颜色、材料种类），使用折线图来表示连续数据（如温度随时间的变化）。

Always label the x-axis and y-axis with the variable name and unit. The independent variable goes on the x-axis and the dependent variable on the y-axis. Use an appropriate scale that makes the graph fill at least half of the grid paper.

始终给 x 轴和 y 轴标上变量名称和单位。自变量放在 x 轴，因变量放在 y 轴。选择合适的刻度，使图表至少占据网格纸的一半空间。

If drawing a line graph, plot points accurately with small crosses and then join them with a ruler. For a line of best fit, do not connect dot-to-dot if there is a clear general trend; instead, draw a single straight line or smooth curve with roughly equal numbers of points on each side.

绘制折线图时，先用小十字精确标出数据点，再用直尺连线。如果存在明显的整体趋势，制作最佳拟合线时不要逐点连接，而是画一条在所有点之间穿过的直线或平滑曲线，使两侧的数据点数量大致相等。

8. Identifying Patterns | 识别规律

Once your graph is complete, describe the pattern or trend clearly. Use phrases like ‘as the independent variable increases, the dependent variable increases/decreases’ and mention if the relationship appears linear (a straight line).

图表完成之后，要清晰地描述其中的规律或趋势。可以使用“随着自变量增大，因变量也随之增大/减小”这样的表述，并说明这种关系是否看起来呈线性（一条直线）。

In many Year 7 investigations, you may see a directly proportional pattern, where doubling the independent variable also doubles the dependent variable. Show this by calculating a simple ratio or by noting that the line passes through the origin.

在 Year 7 的许多探究实验中，你可能会看到正比例规律，即自变量加倍，因变量也加倍。可以通过计算一个简单的比值，或指出图线经过原点来展示这一点。

Be able to use your pattern to make simple predictions, such as reading a value between plotted points (interpolation). While extrapolation (reading beyond the data) is useful, you should mention that it is less certain.

要能够利用规律进行简单预测，例如在已有数据点之间读取数值（内插法）。虽然外推（在数据范围之外读取）也很有用，但你应说明其不确定性较高。

9. Drawing Conclusions | 得出结论

A conclusion must answer the original investigation question or hypothesis. It should be written in complete sentences and refer directly to the data you collected, not just state your opinion.

结论必须回答最初的探究问题或假设。结论要用完整的句子来表述，并直接引用所收集到的数据，而不只是陈述你的个人看法。

For example, instead of writing ‘sugar dissolves faster in hot water’, write ‘The results show that as water temperature increased from 20°C to 60°C, the time taken for 5 g of sugar to dissolve decreased from 120 s to 45 s. Therefore, higher temperature speeds up dissolving.’

例如，不要写“糖在热水中溶解得更快”，而应写“结果表明，当水温从 20°C 升高到 60°C 时，5 g 砂糖完全溶解所需的时间从 120 s 减少到 45 s。因此，较高的温度会加快溶解速度。”

If the data does not support your prediction, you must still write a conclusion based on what actually happened. Acknowledging an unexpected outcome and offering a scientific reason is a higher-level skill.

如果数据不支持你的预测，你仍然必须根据实际发生的情况来写结论。承认意外结果并提出科学上的原因是一项更高层次的技能。

10. Evaluating the Experiment | 评估实验

Evaluation is not about saying ‘the experiment went wrong’. Instead, you reflect on how reliable your results are and how the method could be made more accurate or precise.

评估不是简单地说“实验搞砸了”，而是要反思结果的可靠性程度，以及如何改进方法使其变得更准确或更精密。

Identify specific weaknesses, such as ‘the temperature reading might have been inaccurate because the thermometer was taken out of the water to read’, and then propose a realistic improvement, like ‘use a data logger with a temperature probe so readings are taken continuously without removing it from the liquid’.

要找出具体的不足之处，例如“温度读数可能不准确，因为每次读数时都把温度计从水中拿了出来”，然后提出切实可行的改进方案，比如“使用连接温度探针的数据记录仪，这样可以连续读取温度而不必从液体中取出探针”。

Consider the range of data and number of repeats. A wider range or more repeats would strengthen the conclusion. In an assessment, always suggest collecting more data if time or resources allowed.

考虑数据的范围和重复次数。范围更广或重复次数更多，都能让结论更加有力。在考核中，如果时间或资源允许，总是建议收集更多的数据。

11. Common Mistakes to Avoid | 常见错误避免

Forgetting to include units or writing them inside the results table instead of in the column heading is one of the most frequent errors. Always double-check every number for its correct unit.

忘记写单位，或者把单位写在结果表格内部而不是表头中，这是最常犯的错误之一。一定要仔细核对每个数字是否带上了正确的单位。

Starting the y-axis scale from zero when all your data is clustered between 50 and 60 forces your plotted points into a small area. Instead, begin the axis just below your lowest value to spread the data and reveal trends clearly.

当所有数据都集中在 50 到 60 之间时，却让 y 轴刻度从 0 开始，这会导致数据点挤在一块很小的区域里。正确的做法是从刚低于最低值的地方开始，让数据分散开来，清晰地显示趋势。

Writing a conclusion that is not supported by the data, often because you want your prediction to be right, is a serious error. Always let the data guide your conclusion, even if it is surprising.

由于想让自己的预测成立，而写下一个数据并不支持的结论，这是一个严重的错误。应该始终让数据来引导你的结论，即使结果出人意料也要如实表述。

Using the wrong type of graph, such as a line graph for non-numerical categories, can lose all the marks for the graph presentation section. Check whether your independent variable is continuous or categoric before you decide.

使用错误的图表类型，比如对非数值分类数据也使用折线图，会导致图表展示部分的分数全部丢光。在决定图表类型之前，务必确认你的自变量是连续型还是分类型。

12. Exam-Style Practical Tips | 考试风格实践技巧

Read the practical question several times, underlining the command words such as ‘describe’, ‘explain’, ‘suggest’ and ‘evaluate’. Each command word demands a different style of answer, and your response must match it.

把实践类问题多读几遍，在诸如“描述”“解释”“建议”和“评估”等指令词下画线。每个指令词都要求不同风格的答案，你的回答必须与之匹配。

When asked to plan an investigation, always identify the independent, dependent and at least two control variables before writing the step-by-step method. State how you will ensure safety and which equipment you will use.

当被要求设计一个探究方案时，在写出分步方法之前，一定要先确定自变量、因变量以及至少两个控制变量。并说明你如何确保安全以及会使用哪些仪器。

If a question provides a table of results and asks you to spot the anomaly, calculate the differences between consecutive readings or look for a value that breaks the smooth pattern. Explain your choice in the next part.

如果题目给出一个结果表格并让你找出异常值，可以计算连续读数之间的差值，或者寻找那个打破了平滑规律的数据点。然后在下一问中解释你的判断理由。

Time yourself when practising drawing graphs. In an assessment, you should be able to create a fully labelled graph with an appropriate scale in about five minutes. Practice with real data from your practical notebook.

练习绘制图表时要给自己计时。在考核中，你应该能够在大约五分钟内完成一张带完整标注、比例恰当和刻度的图表。用你实验记录本里的真实数据多加练习。

Published by TutorHao | Science Revision Series | aleveler.com

更多咨询请联系16621398022（同微信）