03 · 电子排布式与轨道表示式

原子结构示意图、电子排布式、电子排布图

价层电子排布式书写规则是处于稳定状态的原子，核外电子将尽可能地按能量最低原理排布

核外电子排布的表示方法	意义	实例（以硫原子为例）
原子结构示意图	表示每个能层容纳的电子数
电子排布式	表示每个能级容纳的电子数	$1\mathrm{s}{\phantom{A}}^{2}2\mathrm{s}{\phantom{A}}^{2}2\mathrm{p}{\phantom{A}}^{6}3\mathrm{s}{\phantom{A}}^{2}3\mathrm{p}{\phantom{A}}^4$
简化的电子排布式	前一周期稀有气体元素符号 $+$ 剩余电子排布式	$[\mathrm{Ne}]3\mathrm{s}{\phantom{A}}^{2}3\mathrm{p}{\phantom{A}}^4$
电子排布图（轨道表示式）	表示每个原子轨道容纳的电子数

孤电子对和价层电子对辨析

辨析对象	意义	实例
孤电子对	在分子或原子团中，未参与成键的成对价电子	如 $\mathrm{H}{\phantom{A}}_2\mathrm{O}$ 中，中心 $\mathrm{O}$ 原子的6个价电子，2 个用于形成共价键，剩余的 4 个价电子即为水中氧原子的两个孤电子对
价层电子对	在分子或原子团中，中心原子的价层电子对 = σ 键电子对 + 孤电子对	如 $\mathrm{H}{\phantom{A}}_2\mathrm{O}$ 中，中心 $\mathrm{O}$ 原子的价层电子对 = 2 个 σ 键电子对 + 2 个孤电子对 = 4

部分元素电子排布式和价层电子轨道表示式

原子序数	元素名称	元素符号	电子（或简化电子）排布式	价层电子轨道表示式
1	氢	$\mathrm{H}$	$1s^1$	$\stackrel{1s}{\boxed{{\displaystyle \uparrow }}}$
2	氦	$\mathrm{He}$	$1s^2$	$\stackrel{1s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
3	锂	$\mathrm{Li}$	$1s^{2}2s^1$	$\stackrel{2s}{\boxed{{\displaystyle \uparrow }}}$
4	铍	$\mathrm{Be}$	$1s^{2}2s^2$	$\stackrel{2s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
5	硼	$\mathrm{B}$	$1s^{2}2s^{2}2p^1$	$\stackrel{2s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{2p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}}$
6	碳	$\mathrm{C}$	$1s^{2}2s^{2}2p^2$	$\stackrel{2s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{2p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}}$
7	氮	$\mathrm{N}$	$1s^{2}2s^{2}2p^3$	$\stackrel{2s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{2p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}}$
10	氖	$\mathrm{Ne}$	$1s^{2}2s^{2}2p^6$	$\stackrel{2s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{2p}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}}$
11	钠	$\mathrm{Na}$	$1s^{2}2s^{2}2p^{6}3s^1$	$\stackrel{3s}{\boxed{{\displaystyle \uparrow }}}$
12	镁	$\mathrm{Mg}$	$1s^{2}2s^{2}2p^{6}3s^2$	$\stackrel{3s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
13	铝	$\mathrm{Al}$	$1s^{2}2s^{2}2p^{6}3s^{2}3p^1$	$\stackrel{3s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{3p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}}$
14	硅	$\mathrm{Si}$	$1s^{2}2s^{2}2p^{6}3s^{2}3p^2$	$\stackrel{3s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{3p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}}$
18	氩	$\mathrm{Ar}$	$1s^{2}2s^{2}2p^{6}3s^{2}3p^6$	$\stackrel{3s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{3p}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}}$
19	钾	$\mathrm{K}$	$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^1$	$\stackrel{4s}{\boxed{{\displaystyle \uparrow }}}$
20	钙	$\mathrm{Ca}$	$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^2$	$\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
21	钪	$\mathrm{Sc}$	$[\mathrm{Ar}]3d^{1}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
22	钛	$\mathrm{Ti}$	$[\mathrm{Ar}]3d^{2}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
23	钒	$\mathrm{V}$	$[\mathrm{Ar}]3d^{3}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
24 *	铬	$\mathrm{Cr}$	$[\mathrm{Ar}]3d^{5}4s^1$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}}\stackrel{4s}{\boxed{{\displaystyle \uparrow }}}$
25	锰	$\mathrm{Mn}$	$[\mathrm{Ar}]3d^{5}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
26	铁	$\mathrm{Fe}$	$[\mathrm{Ar}]3d^{6}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
27	钴	$\mathrm{Co}$	$[\mathrm{Ar}]3d^{7}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
29 *	铜	$\mathrm{Cu}$	$[\mathrm{Ar}]3d^{10}4s^1$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{4s}{\boxed{{\displaystyle \uparrow }}}$
30	锌	$\mathrm{Zn}$	$[\mathrm{Ar}]3d^{10}4s^2$	$\stackrel{3d}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}$
31	镓	$\mathrm{Ga}$	$[\mathrm{Ar}]3d^{10}4s^{2}4p^1$	$\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{4p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}\boxed{{\displaystyle {}_{}^{{}^{}}}}}$
32	锗	$\mathrm{Ge}$	$[\mathrm{Ar}]3d^{10}4s^{2}4p^2$	$\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{4p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle {}_{}^{{}^{}}}}}$
33	砷	$\mathrm{As}$	$[\mathrm{Ar}]3d^{10}4s^{2}4p^3$	$\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{4p}{\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}\boxed{{\displaystyle \uparrow }}}$
36	氪	$\mathrm{Kr}$	$[\mathrm{Ar}]3d^{10}4s^{2}4p^6$	$\stackrel{4s}{\boxed{{\displaystyle \uparrow \downarrow }}}\stackrel{4p}{\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}\boxed{{\displaystyle \uparrow \downarrow }}}$
37	铷	$\mathrm{Rb}$	$[\mathrm{Kr}]5s^1$	$\stackrel{5s}{\boxed{{\displaystyle \uparrow }}}$

*特殊情况：$\mathrm{Cr}:[\mathrm{Ar}]3d^{5}4s^1$，$\mathrm{Cu}:[\mathrm{Ar}]3d^{10}4s^1$

过渡金属阳离子

过渡金属阳离子失去电子时从最外层电子开始失去：

• $\mathrm{Fe}:[\mathrm{Ar}]3d^{6}4s^2$

  ${\mathrm{Fe}}^{2+}:[\mathrm{Ar}]3d^6$

  ${\mathrm{Fe}}^{3+}:[\mathrm{Ar}]3d^5$

• $\mathrm{Cu}:[\mathrm{Ar}]3d^{10}4s^1$

  ${\mathrm{Cu}}^{+}:[\mathrm{Ar}]3d^{10}$

  ${\mathrm{Cu}}^{2+}:[\mathrm{Ar}]3d^9$

• $\mathrm{Zn}:[\mathrm{Ar}]3d^{10}4s^2$

  ${\mathrm{Zn}}^{2+}:[\mathrm{Ar}]3d^{10}$