The discussion centers on the nature of coordinate bonds, specifically addressing why the H+ ion does not acquire a negative charge when it accepts a lone pair of electrons from nitrogen in the ammonium ion (NH4+). Participants explore theoretical aspects of bonding, charge distribution, and electron sharing in the context of ammonia and related compounds.
Participants do not reach a consensus on the nature of the bonding and charge distribution in NH4+. Multiple competing views remain regarding the behavior of H+ and the interpretation of electron sharing versus transfer.
There are limitations in the discussion regarding assumptions about electron sharing, the definitions of ionic versus covalent bonds, and the treatment of charge conservation in molecular structures.
I understand everything except this point 'Add the 2 non-bonding 1s electrons and you have 6 total electrons assigned to nitrogen for the sake of formal charge.' Add to which atom the 2 non-bonding 1 s electrons? Could you simplify your point, please?TeethWhitener said:It will also get 3 protons (in the case of NH3) or 4 protons (in the case of NH4+). For simplicity, in the case of NH3, N will share 3 of its electrons with 3 hydrogen atoms (each with 1 electron and 1 proton). It doesn't take the hydrogens' electrons from them (at least not entirely--see below). If it did, then you would write ammonia's formula as N3-(H+)3. Covalent bonds involve sharing of electrons. The 3 electrons from the hydrogens serve to complete the nitrogen's octet, but they don't count toward the formal charge. For the formal charge, each covalent bond counts as one electron.
So for NH4+, there are 4 covalent bonds around nitrogen; therefore there are 8 (4x2) valence electrons satisfying the nitrogen's octet, but only 4 valence electrons counting toward nitrogen's formal charge. Add the 2 non-bonding 1s electrons and you have 6 total electrons assigned to nitrogen for the sake of formal charge. Since nitrogen has 7 protons, the formal charge on nitrogen is +1.
(Caveat: there is some polarity in the N-H bond. That is, a given electron is more likely to be found around the nitrogen in an N-H bond than the hydrogen. However, it is far from being a complete charge transfer.)
No, add as in 4+2=6. You have 4 electrons from nitrogen participating in bonding in NH4+. You have 2 electrons in the 1s orbital of nitrogen (these electrons are not valence electrons: they don't participate in bonding). You add 4+2 to get 6 electrons assigned to nitrogen. Since nitrogen has 7 protons (this is always true--otherwise it's not nitrogen), its formal charge is 7-6 = +1.HCverma said:Add to which atom the 2 non-bonding 1 s electrons?