Answer is: the ratio of amount NaOH reacting per unit amount FeCl₃ is 3 mol NaOH /1 mol FeCl₃.
Balanced chemical reaction:
3NaOH(aq) + FeCl₃(aq) → 3NaCl(aq) + Fe(OH)₃(s).
NaOH is sodium hydroxide.
FeCl₃ is iron(III) chloride.
Coefficient for sodium hydroxide is three and for iron(III hydroxide is one.
Sodium phosphate has a chemical formula
Na2PO4
Calculating the concentration of sodium phosphate given a concentration of sodium ions can be done using dimensional analysis
0.60 moles/L Na+ (1 mole Na2PO4 / 2 moles Na+) = 0.30 moles/L Na2PO4
= .030 M Na2PO4
The pH of the solution : 12
<h3>Further explanation</h3>
Reaction
HCOOH + NaOH ⇒ HCOONa + H₂O
mol HCOOH =

mol NaOH =

Mol NaOH>mol HCOOH ⇒ at the end of the reaction there will be a strong base remains from mol NaOH, so that the pH is determined from [OH⁻]
ICE method :
HCOOH + NaOH ⇒ HCOONa + H₂O
4 5
4 4 4 4
0 1 1 1
Concentration of [OH⁻] from NaOH :

pOH=-log[OH⁻]
pOH=-log 10⁻²=2
pH+pOH=14
pH=14-2=12