8.
下列反应中,其中不属于氧化还原反应的是( )
\(\rm{①3Cl_{2}+6KOH=5KCl+KClO_{3}+3H_{2}O}\)
\(\rm{②2NO_{2}+2NaOH=NaNO_{3}+NaNO_{2}+H_{2}O}\)
\(\rm{③Mg+HCl=MgCl_{2}+H_{2}↑}\)
\(\rm{④SnCl_{4}+2H_{2}O=SnO_{2}+4HCl}\)
\(\rm{⑤4NH_{3}+5O_{2}\dfrac{{催化剂}}{{\triangle }}4NO+6H_{2}O}\)
\(\rm{⑥CaO+H_{2}O=Ca(OH)_{2}}\).