The 4f subshell of an atom contains 10 electrons. What is the maximum number of electrons having spin in the same direction ?

Explanation

To determine the maximum number of electrons in the 4f subshell that can have their spins in the same direction, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the 4f subshell**: The 4f subshell consists of 7 orbitals. Each orbital can hold a maximum of 2 electrons, one with spin-up (+1/2) and one with spin-down (-1/2).

2. **Understand the filling of orbitals**: According to Hund's rule, electrons will fill each orbital singly before pairing up. This means that each of the 7 orbitals will first get one electron with the same spin direction.

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