Answer:
NaF
Step-by-step explanation:
Electronic configuration of Sodium is as follow,
Na = 11 = 1s², 2s², 2p⁶, 3s¹
As shown in electronic configuration, Sodium has 1 valence electrons in its valence shell. Therefore, to complete its noble gas configuration it donates one electron form Na⁺.
Na⁺ = 1s², 2s², 2p⁶
Electronic configuration of Fluorine is as follow,
F = 9 = 1s², 2s², 2p⁵
As shown in electronic configuration, fluorine has 7 valence electrons in its valence shell. Therefore, to complete its noble gas configuration it accepts one electron from Na to form F⁻.
F⁻ = 1s², 2s², 2p⁶
Henec, in order to form a neutral molecules, one Na⁺ combines with one F⁻ to form NaF.