A covalent bond . ANSWER Unselected is always one more bond than the valence number for the pair Sure I AM SURE is the sharing of a pair of valence electrons by two atoms Unselected is a weak chemical bond Unselected is the transfer of a valence electron to an atom that has an unfilled valence shell Unselected always forms a crystal salt

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Electron equations of the given changes are as follow,a)                              cu      →      cu⁺²  + 2e⁻b)                              mg⁺²  +  2 e⁻      →      mgc)                              cl⁻    →      cl  +  1e⁻d)                              s  +  2 e⁻    →      s²⁻e)                                o²⁻      →      o  +  2 e⁻f)                              p  +  3 e⁻    →      p³⁻g)                              fe²⁺    →      fe³⁺  + 1 e⁻h)                              s²⁻    →      s⁴⁺  +  6 e⁻

Answerreleasing energy.;

It's about -20°c to -15°c.