Question

which is the electron configuration for lithium?
1s²
2s³
1s²2s¹
1s¹2s²

Explanation:

): $1s^2$

Step3: Remaining electron to 2s orbital

1 electron left, fills the 2s orbital: $2s^1$

Step4: Combine orbitals

Combine to get full configuration: $1s^22s^1$

Answer:

): $1s^2$

Step3: Remaining electron to 2s orbital

1 electron left, fills the 2s orbital: $2s^1$

Step4: Combine orbitals

Combine to get full configuration: $1s^22s^1$