The electron that is transferred to form Li⁺ from a lithium atom comes from the 2s orbital.

Here's why:

* Lithium's Electron Configuration: Lithium has an electron configuration of 1s² 2s¹. This means it has two electrons in the first energy level (1s) and one electron in the second energy level (2s).

* Ionization: When lithium loses an electron to become a positively charged ion (Li⁺), it loses the electron that is furthest from the nucleus and easiest to remove. This is the electron in the 2s orbital.

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