Question

which characteristic is given by the principal quantum number?
orbital size
orbital mass
orbital shape
orbital orientation

Explanation:

The principal quantum number (\(n\)) in atomic theory determines the energy level and the size of the orbital. Orbital mass is not a characteristic defined by quantum numbers. Orbital shape is determined by the azimuthal quantum number (\(l\)), and orbital orientation is determined by the magnetic quantum number (\(m_l\)). So the principal quantum number gives the orbital size.

Answer:

A. orbital size