It is possible that Kr and Ar could also act as Lewis bases, but evidently they cannot compete with HF.

很可能氪和氩也可以做路易斯碱，但显然它们不能和氟化氢竞争。

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The first ionization potentials are as follows: He, 24.6; Ne, 21.6; Ar, 15.8; Kr, 14.0; Xe, 12.1; and Rn, 10.7 eV.

稀有气体的第一电离势是这样的：He 24.6; Ne 21.6; Ar 15.8; Kr 14.0; Xe 12.1; Rn 10.7 eV。

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