MCQ
The most probable radius (in pm) for finding the electron in $H{e^ + }$ is
  • A
    $0.0$
  • B
    $52.9$
  • $26.5$
  • D
    $105.8$

Answer

Correct option: C.
$26.5$
c
(c) Most probable radius $= a_0 / Z$

where $a_0 = 52.9\, pm. $ For helium ion, $Z = 2.$

$rmp = $ $\frac{{52.9}}{2}$ $= 26.45\, pm.$

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