I am studying for my Chemistry final right now, and I am puzzled by this particular question:
"When hydrocyanic acid (HCN) is added to sodium hydroxide (NaOH), what is the net ionic equation for the reaction that occurs?"
I thought that the answer would simply be
However, the correct answer is
HCN + OH-
Earlier in the course, we were taught that the net ionic equation for any reaction considers aqueous compounds as anions and cations, and therefore if a part of the aqueous compound doesn't react that part stays out of the net ionic equation. Wouldn't that be the case for HCN, since the CN-
part of HCN doesn't change? The only reason I could see why that is is that HCN is such a weak acid with a small pKa value that it barely dissociates. If that is the reason why I got this problem wrong, then my question is at what specific pKa value do we no longer consider the dissociation of acids?