Answer:
Option 10. 1
Explanation:
The unbalanced equation is:
Fe₂P(s) + S(s) → P₄S₁₀(s) + FeS(s)
In order to balance P, we can add 4 to the Fe₂P.
The addition made that we get 8 Fe now, in the reactant side, so we add 8 to FeS in product side.
We count the sulfur, 10 from the P₄S₁₀ + 8 from the FeS = 18
We add 18 to the S in the reactant side. Balanced equation is:
4Fe₂P(s) + 18 S(s) → P₄S₁₀(s) + 8 FeS(s)
