Answer:
Final [B] = 1.665 M
Explanation:
3A + 4B → C + 2D
Average rection rate = 3[A]/Δt = 4[B]/Δt = [C]/Δt = 2[D]/Δt
0.05600 M/s = 4 [B]/ 2.50 s
[B] = 0.035 M (concentration of B consumed)
Final [B] = initial [B] - consumed [B]
Final [B] = 1.700 M - 0.035 M
Final [B] = 1.665 M
A) 2H₂(g) + O₂(g) → 2H₂O(l) + 285.83 kJ
Exothermic
B) 2Mg + O₂ → 2MgO + 1200kJ
Exothermic
It would cause a drop <span>but I am not sure double check other answers </span>