Question Detail
Question
What is the condensed electron configuration for lithium?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Condensed electron configuration uses the symbol of the nearest noble gas of lower atomic number in brackets to represent the core electrons. Lithium (atomic number 3) has the configuration 1s² 2s¹. The nearest noble gas with lower atomic number is helium (He, atomic number 2) with configuration 1s². The condensed configuration is [He] 2s¹.
Hint
Identify the noble gas that precedes lithium and write its symbol in brackets, then add the remaining electrons.