Answer:
6 Li(s) + N₂(g) → 2 Li₃N(s)
Explanation:
Solid lithium metal and diatomic nitrogen gas react spontaneously to form a solid product (lithium nitride). The chemical equation is:
Li(s) + N₂(g) → Li₃N(s)
Since the atomicities in the product are odd, the easiest way to balance the equation is by first multiplying it by 2.
Li(s) + N₂(g) → 2 Li₃N(s)
The final (balanced) equation is:
6 Li(s) + N₂(g) → 2 Li₃N(s)