The net ionic equation is as below
H^+(aq) + H^-(aq) → H2O(l)
Explanation
from the chemical equation
HClO4(aq) + NaOH (aq) → H2O(l) + NaClO4(aq)
write ionic equation
that is,
H^+(aq)+ClO4^-(aq) + Na^+(aq) +OH^-(aq)→ H2O(l) + Na^+(aq)+ClO4^-(aq)
cancel the spectator ions in both side(ions that do no take place in a chemical equation)
that ClO4^- and Na^+
the net ionic is therefore
= H^+(aq) + OH^-(aq) → H2O(l)
I think Magnesium not sure because the relative atomic mass of magnesium is 24,31.
2250cm3= 2250/1000000m3=.00225m3