The Haber Process synthesizes ammonia at elevated temperatures and pressures. Suppose you combine $1580$ L of nitrogen gas and $4000$ L of hydrogen gas at STP$,$ heat the mixture to run the reaction, then separate the ammonia from the reaction mixture. What volume of reactant, measured at STP$,$ is left over? Assume the reaction goes to completion.

N$($g$)+3$ H$($g$)->2$ NH$($g$)$