Balancing Chemical Equations

Question

Using your knowledge of chemical formulas and writing balanced chemical equations, write a balanced chemical equation when decasulfur tribromide gas reacts with solid selenium to form bromine gas and selenium sulfide gas. Once you have written a balanced chemical equation, determine how much selenium sulfide would be produced if we had 4.96 moles of bromine gas.

Answer 1

2S₁₀Br_3(g) + 10Se_(s) ----> 3Br_2(g) + 10SeS_2(s)

Once we write the equation we see right away that we would need 2 equivalents of S₁₀Br₃ to form 3 of Br₂ by simply balancing it. Also, this would require 10 eq. of Se(s). Finally, we have a 10/3 molar ratio between SeS₂ and Br₂ which would give us 16.53 moles of SeS₂. We multiply by the molar mass (143.09 g/mol) and we get 2365.8 g of SeS₂.