A Nitrogen got 7 electrons, which means every Nitrogen got 3 pairs of electrons and 1 single electron, ready to be shared.
A second nitrogen come with the same amount of electrons, 3 pairs and 1 single ready to shared.
The 2 nitrogens put in common their single electrons to create a pair.
Which means, that 1 pair of electron is shared between the nitrogens in a molecule of N2
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