Question

which is the noble - gas notation for lead (pb)?
rn6s²4f¹⁴5d¹⁰6p²
rn6s²5d¹⁰6p²
xe6s²4f¹⁴5d¹⁰6p²
xe6s²5d¹⁰6p²

Explanation:

• Lead (\(Pb\)) has an atomic number of \(82\).
• The noble - gas notation uses the previous noble gas. Xenon (\(Xe\)) has an atomic number of \(54\), while radon (\(Rn\)) has an atomic number of \(86\) which is higher than \(Pb\)'s atomic number. So we use \(Xe\) as the noble - gas core.
• After \(Xe\), the electron configuration is \(6s^{2}4f^{14}5d^{10}6p^{2}\) (following the Aufbau principle: filling \(6s\) first (\(n = 6,l = 0\)), then \(4f\) (\(n=4,l = 3\)), then \(5d\) (\(n = 5,l=2\)) and finally \(6p\) (\(n = 6,l = 1\))).

Answer:

\(\text{[Xe]}6s^{2}4f^{14}5d^{10}6p^{2}\) (the third option)