Answer
(a) $2K(s) + 2H_{2}O(l) -> 2KOH(aq) + H_{2}(g)$
(b) $NaH(s) + H_{2}O(l) -> NaOH(aq) + H_{2}(g)$
(c) $2Na(s) + O_{2}(g) -> Na_{2}O_{2}(s)$
(d) $K(s) + O_{2}(g) -> KO_{2}(s)$
Work Step by Step
Balancing the chemical equations so that the same number of each element are on both sides of the equation:
(a) $2K(s) + 2H_{2}O(l) -> 2KOH(aq) + H_{2}(g)$
(b) $NaH(s) + H_{2}O(l) -> NaOH(aq) + H_{2}(g)$
(c) $2Na(s) + O_{2}(g) -> Na_{2}O_{2}(s)$
(d) $K(s) + O_{2}(g) -> KO_{2}(s)$
