Question

The reaction of sulphur in alkaline medium is the below:
$S_{8(s)}+aO{H}_{(aq)}^{-}\to b{S}_{(aq)}^{2-}+c{S}_2{O}_3{}^{2-}(aq)+d{H}_2{O}_{(\ell )}$
The values of '$a$' is

Answer 1

Answer: 12

for balancing in basic medium add equal number of $O{H}^{\ominus }$ that of $H^{+}$
$2S_8+12H_{2}O+24O{H}^{\ominus }⟶8S^{2-}+4S_2{O}_8^{2-}+24H_{2}O$
$2S_8+24O{H}^{\ominus }\to 8S^{2-}+4S_2{O}_8^{2-}+12H_{2}O$
$S_8+12O{H}^{\ominus }\to 4S^{2-}+2S_2{O}_8^{2-}+6H_{2}O$
$a=12$