Write the net ionic equation and list the spectators for the reaction KF (aq) + HgNO3 (aq) 

Answer 1

This can be a little tricky, especially if this is a question in something other than intro chem. I'll try to provide both types of answers, depending on the level of chemistry being considered:

Intro level (and probably incorrect)...

KF(aq) + HgNO₃(aq) ==> KNO₃(aq) + HgF(s) ... molecular equation

Hg⁺(aq) + F^-(aq) ==> HgF(s) ... net ionic equation

Spectator ions: K⁺ and NO₃^-

More advanced level:

HgNO₃ would actually exist as Hg₂(NO₃)₂

Hg₂(NO₃)₂(aq) + 2KF(aq) ==> 2KNO₃(aq) + Hg₂F₂ =H₂O=> Hg(s) + HgO(s) + 2HF(aq) ... molecular

2Hg⁺(aq) + 2F^-(aq) + H₂O(l) ==> Hg(s) + HgO(s) + 2HF(aq) ... net ionic

Spectator ions: K⁺ and NO₃^-