Final answer:
The question is about calculating the equilibrium concentration of HBr given the equilibrium constant and the concentration of Br2. The H2 concentration is the same as Br2 due to the 1:1 mole ratio, and since Keq is very high, the HBr concentration will be much greater than H2 and Br2 at equilibrium.
Step-by-step explanation:
The student asks to calculate the equilibrium concentration of HBr. Given the equilibrium constant (Keq) of 2.18 × 106 and the equilibrium concentration of Br2 as 0.00243 M, we can deduce that the H2 concentration will also be 0.00243 M because the mole ratio of H2 to Br2 is 1:1 in the equilibrium reaction.
The equilibrium expression for the reaction H2 + Br2 → 2HBr is given by:
Keq = \([\frac{[HBr]^2}{[H2][Br2]}\)
After arranging the equation to solve for the equilibrium concentration of HBr, we substitute the known equilibrium values:
(2.18 × 106) = \([\frac{[HBr]^2}{(0.00243)(0.00243)}\])
Then we solve for [HBr2] and take the square root to find [HBr]. Considering the high value of Keq, the concentration of HBr will be much greater than that of H2 and Br2 at equilibrium.