Which net ionic equation describes the reaction between NAOHAQ & HCLAQ

the net equation that describe the reaction  between NaOH(aq) and HCL(aq)  is as below

write the  chemical equation

NaOH(aq) +HCl  (aq)  = NaCl(aq)  + H2O (l)

ionic equation

Na^+(aq)  + OH^-(aq)  + H^+(aq)  + Cl^-(aq)  = Na^+ (aq) + Cl^-9aq)  +H20(l)

cancel the spectators  ion (ion that do not take place in a chemical equation )

that  is Na^+  and  Cl^- ions

the  net ionic equation is therefore

= H^+(aq)  + OH^-(aq)  =  H20 (l)

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-