1. Find Hafnium on the periodic table. It's in period 6, group 4.
2. Identify the preceding noble gas. The noble gas before Hafnium is Xenon (Xe).
3. Write the noble gas symbol in brackets. [Xe]
4. Determine the remaining electron configuration. Hafnium has 72 electrons. Xenon has 54 electrons. Therefore, the remaining configuration is 4f¹⁴ 5d² 6s².
The noble gas notation for Hafnium is [Xe] 4f¹⁴ 5d² 6s²
