In the reaction between the strong acid hci and the strong base naoh which of the ions listed below is a spectator ion?

na+
h+
h3o+
oh-

Na+

Explanation:

The equation would be:

HCl (aq) + NaOH (aq) --> HOH (l) + NaCl (aq)

The equation is already balanced and the NaCl will disassociate in Na+ and Cl- and HCl will disassociate into H+ and Cl- and NaOH will disassociate into Na+ and OH-. Na+ is on both sides of the equation and stays the same, so Na+ will be the spectator ion.  

there is none because earth is stationary and flat.