Label the molecular orbitals formed by the following combinations of atomic orbitals if Z-axis is the internuclear axis.
` 1 s - 1s`

Explanation

To label the molecular orbitals formed by the combination of two 1s atomic orbitals along the z-axis, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Atomic Orbitals**:
- We have two 1s atomic orbitals from two different atoms.

2. **Determine the Orientation**:
...