All atoms have octets, sulfur has 2 single and one double bonded oxygen. Oxygen is single bonded in this depiction. When 8 vse are introduced into 7 orbitals, then one set of spin-paired electrons results, leaving six unpaired electrons. The orbital diagram would relate these values to 7 dashes on a line. Barium hydroxide contains two hydroxide anions.
Phosphoric acid contains three hydrogen ions.
A limiting reagent type of problem. Barium hydroxide is present in excess, phosphoric acid is limiting reagent. No more than 0.116 mole water can form.