What ion is formed when an atom of mercury (hg) loses two electrons? hg–1 hg–2 hg+1 hg+2

The ion formed when mercury looses two electrons is Hg^2+

An ion is formed when a chemical specie looses or gains electrons. The ion is positive if electrons are lost and the ion is negative when electrons are gained.

Mercury is a metal hence it is electropositive. It looses electrons easily. As such, when mercury looses two electrons, it forms the ion Hg^2+.

Hence, when mercury looses two electrons, it forms Hg^2+

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