[samiam]

So COOH-->COO^- + H^+
why is the molecule now negative because we treat H as a proton? so now COO has one less proton so more electrons giving it a negative charge?

[samiam]

So COOH-->COO^- + H^+
why is the molecule now negative because we treat H as a proton? so now COO has one less proton so more electrons giving it a negative charge?

also if nitrogen can only form 3 bonds how can H3N⁺-C exist in amino acids..

[rabolisk]

Charges have to balance out. If you take a proton from a neutral molecule, the remaining molecule has to have a charge of -1, since -1 + 1 = 0.

Who told you that nitrogen can only form 3 bonds?

[vmelkon]

3 bonds is common for nitrogen in a lot of cases but there are others. The best example is the entire set of oxides of nitrogen : N2O, NO, NO2, N2O3, N2O4, N2O5.

Another example, the nitrate ion, nitrogen has 5 bonds.

[rabolisk]

Nitrate ion has 4 bonds, not 5.