Lithium and Nitrogen React in a Combination Reaction to Produce

Multiple Choice

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6Li (s) + N₂ (g) → 2Li₃N (s)
How many moles of lithium are needed to produce 0.45 mol of Li₃N when the reaction is carried out in the presence of excess nitrogen?

A) 0.23
B) 1.4
C) 0.15
D) 0.30
E) 2.7