混合物的分离
Separating Mixtures
针对不同类型的混合物，选择并实施合适的分离技术：过滤（分离不溶性固体）、蒸馏（根据沸点分离液体）、结晶（分离溶解固体）和色谱法（分离有色物质）。
Select and carry out appropriate separation techniques for different types of mixtures: filtration (insoluble solids), distillation (liquids by boiling point), crystallisation (dissolved solids), and chromatography (coloured substances)
学习证据 / Evidence
- 能针对给定的混合物选择正确的分离技术，并说明理由
- 能描述简单蒸馏的步骤，并解释其原理
- 能解读色谱结果（Rf值、组分数量）
- 能解释为什么过滤能从水中去除沙子，但不能去除盐
- Selects the correct separation technique for a given mixture with justification
- Describes the steps of simple distillation and explains why it works
- Interprets a chromatography result (Rf values, number of components)
- Explains why filtration removes sand from water but not salt
评估问题 / Assessment
如果{{name}}需要把混合在水中的沙和盐分开，他们能否描述两个分离步骤、所需设备，并解释每一步为何有效？
If {{name}} needed to separate salt from sand mixed together in water, could they describe two stages of separation, the equipment needed, and explain why each step works?