Editing Openai/6946f4fa-e8bc-800b-b77e-c62f6390a97c (section)

=== （Molecular Orbital Theory） ===

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===== a. 0 =====
b. 0.5
c. 1
d. 1.5
e. 2

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Bond order=Nbonding−Nantibonding2\text{Bond order} = \frac{N_\text{bonding} - N_\text{antibonding}}{2}Bond order=2Nbonding−Nantibonding

===== - 每個 He 原子：2 電子 =====
* He₂：4 電子
* He₂⁺：少 1 電子 → 3 電子

===== 對 He₂ 類型（只考慮 1s 軌域）： =====

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===== BO=2−12=0.5\text{BO} = \frac{2 - 1}{2} = \boxed{0.5}BO=22−1=0.5 =====

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===== I. Be₂ is more stable because it contains both bonding and antibonding valence electrons. =====
II. H₂ has a higher bond order than Be₂.
III. H₂ is more stable because it only contains σ1s electrons.
IV. H₂ is more stable because it is diamagnetic, whereas Be₂ is paramagnetic.

===== a. I, II =====
b. III only
c. II, III
d. II, III, IV
e. III, IV

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====== - 電子數：2 ======
* 填入：σ1s²
* 鍵階：

(2−0)/2=1(2 - 0)/2 = 1(2−0)/2=1
* 穩定、抗磁性

====== - 每個 Be：2s² → 總 4 電子 ======
'' 填入： - σ2s² - σ''2s²
* 鍵階：

(2−2)/2=0(2 - 2)/2 = 0(2−2)/2=0
* 幾乎不穩定（實際上幾乎不存在）

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: 

❌ 錯
反鍵電子會降低穩定性

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✔ 正確（1 > 0）

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✔ 正確

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❌ 錯
'' Be₂：σ2s² σ''2s² → 抗磁性
* 不是順磁性

===== II, III\boxed{\text{II, III}}II, III =====

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