📚 Mastering Periodicity, Group 2 and the Halogens | 精通周期性、第2族与卤素
This article is a complete Unit 3 revision guide for A-Level Chemistry students aiming for top grades. It systematically covers the three most heavily examined topics in the inorganic chemistry portion of Unit 3: periodicity across Period 3, the characteristic chemistry of Group 2 elements, and the reactions and trends of the Group 17 halogens. Every section is written in precise exam language, with common misconceptions and examiner traps highlighted throughout.
本文是面向冲击 A-Level 化学高分的 Unit 3 完整复习指南，系统讲解 Unit 3 无机化学部分三大高频考点：第三周期元素的周期性规律、第2族元素的特征化学，以及第17族卤素的反应与递变规律。每个板块均采用标准化考试语言撰写，并全程标注常见误区与考官陷阱。
1. The Structure of the Periodic Table | 元素周期表的结构
The periodic table arranges elements in order of increasing atomic number, Z. Elements in the same period share the same number of occupied electron shells, while elements in the same group share the same number of outer-shell electrons and therefore show similar chemical properties. Periodicity refers to the repeating pattern of physical and chemical properties across each period.
元素周期表按照原子序数 Z 的递增顺序排列元素。同一周期的元素具有相同的电子层数，同一族的元素具有相同的最外层电子数，因此表现出相似的化学性质。"周期性"指同一周期内元素
Published by TutorHao | Exam Prep Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
或截图后用「扫一扫 → 相册」选择本图