这些概念如何连接
好的科学页面应让概念之间的联系清晰可见，而不是只罗列定义。
周期趋势
原子半径
电离能
电负性
值得注意
好的科学页面应让概念之间的联系清晰可见，而不是只罗列定义。
Mendeleev
元素周期表 · 化学 · 物理
深入理解
周期趋势
核心概念
先抓住核心概念，再把它与具体元素、测量和实验联系起来。
Take one idea at a time. If a new word appears, connect it to a concrete object, number or experiment before moving on.
Say the idea aloud in your own words, then test it with a simple example.
Memorising a sentence is not the same as understanding the mechanism behind it.
检查理解
Start with the central idea, then test it against a concrete element or example. A scientific model is useful when we know what it explains — and where its limits are.