Hydrogen atom: What is the radius of the smallest electron orbit in a singly-ionized helium atom?

Question

Quizplus · Accepted Answer

The radius of an electron orbit in a hydrogen atom is given by the Bohr radius, which is equal to 0.529 Å. In a singly-ionized helium atom (He+), there is only one electron remaining. The radius of the smallest electron orbit in He+ can be calculated using the formula r = (n^2 / Z) * a0, where n is the principal quantum number (n=1 for the smallest orbit), Z is the nuclear charge (Z=2 for He+), and a0 is the Bohr radius. Plugging in these values gives r = (1^2 / 2) * 0.529 Å, which simplifies to r = 0.265 Å, or 2.65 × 10^-11 m (choice B).

Hydrogen Atom: What Is the Radius of the Smallest Electron