The electron configuration for lithium [tex]1s^{2} 2s^{1}[/tex]. So, the correct answer is C.
Electronic configuration:-
The electron configuration of an element describes how electrons are distributed in its atomic orbitals. Electron configurations of atoms follow a standard notation in which all electron-containing atomic subshells (with the number of electrons they hold written in superscript) are placed in a sequence.
Electronic configuration for lithium:-
The atomic number of lithium is 3. So, the electronic configuration is as follows:-
[tex]Li= 1s^{2} 2s^{1}\\=(He) 2s^{1}[/tex]
So, the correct option is C.
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