Year 7 Cambridge Chemistry: Case Study Practical Drills | Year 7 剑桥化学：案例分析实战演练

📚 Year 7 Cambridge Chemistry: Case Study Practical Drills | Year 7 剑桥化学：案例分析实战演练

Applying chemistry knowledge to real-world scenarios is the best way to master the subject. This article provides ten case study drills covering key topics from the Year 7 Cambridge syllabus, including separation techniques, acids and alkalis, rusting, physical and chemical changes, gas tests, chromatography, purity, classification of matter, neutralisation and water purification.

将化学知识应用到实际情境中是掌握这门学科的最佳方法。本文提供了十个案例分析演练，涵盖 Year 7 剑桥课程大纲中的重点主题，包括分离技术、酸和碱、生锈、物理变化与化学变化、气体检验、色谱法、纯度、物质分类、中和反应以及水的净化。

1. Separating Sand, Salt and Water | 案例一：分离沙子、食盐和水

You are given a beaker containing a mixture of sand, common salt (sodium chloride) and water. Sand is insoluble in water, while salt is soluble. Your goal is to obtain dry sand and pure salt crystals.

你得到一个盛有沙子、食盐（氯化钠）和水的烧杯。沙子不溶于水，而食盐可溶。你的目标是得到干燥的沙子和纯净的食盐晶体。

Step 1: Filtration – Pour the mixture through a filter funnel lined with filter paper. The insoluble sand is trapped on the paper as the residue, while the salt solution (filtrate) passes through.

步骤一：过滤——将混合物通过铺有滤纸的过滤漏斗。不溶的沙子作为残渣留在滤纸上，而食盐水溶液（滤液）则透过滤纸。

更多咨询请联系16621398022（同微信）