Question

what is the missing coefficient to make a balanced equation? n₂ + ?k → k₃n

Explanation:

Step1: Balance nitrogen atoms

On the left - hand side, we have 2 nitrogen atoms in $N_2$. On the right - hand side, each $K_3N$ has 1 nitrogen atom. So, to balance nitrogen, we need 2 moles of $K_3N$.

Step2: Balance potassium atoms

Since we have 2 moles of $K_3N$ on the right - hand side, which means we have $2\times3 = 6$ potassium atoms. On the left - hand side, each $K$ has 1 potassium atom. So we need 6 moles of $K$.
The balanced equation is $N_2+6K
ightarrow2K_3N$.

Answer:

The coefficient of $K$ is 6 and the coefficient of $K_3N$ is 2.