Question

The principal quantum number (n) and magnetic quantum number (m_l) for the valence electrons of rubidium atom (Z = 37) are ____________ respectively.

Options

• 5, 0

• 4, 0

• 5, 1

• 5, +1

Answer 1

The principal quantum number (n) and magnetic quantum number (m_l) for the valence electrons of rubidium atom (Z = 37) are 5, 0 respectively.

Explanation:

Rubidium (Z = 37) → 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹

So, last electron enters 5s orbital.

Hence, n = 5 and m_l = 0.