Consider the chemical equation. 2nbr3 + 3naoh mc008-1.jpg n2 + 3nabr + 3hobr if there are 40 mol of nbr3 and 48 mol of naoh, what is the excess reactant?

Answer is: NBr₃ is the excess reactant.

Balanced chemical reaction: 2NBr₃ + 3NaOH → N₂ + 3NaBr + 3HBrO.

n(NBr₃) = 40 mol; amount of substance.

n(NaOH) = 48 mol.

From chemical reaction: n(NBr₃) : n(NaOH) = 2 : 3.

40 mol : n(NaOH) = 2 : 3.

n(NaOH) = 60 mol; for 40 moles of NBr₃, 60 moles of NaOH is needed, because there is only 48 moles, not all NBr₃ will react (onl 32 moles, 16 moles are excess).