We use an ICE table to solve for equilibrium concentrations when given initial concentrations and the equilibrium constant, K. For each case below, determine the best approach to solve for x using the value of K and the expression of K with x. "x" represent the smallest positive change.

K expression K value Solving approach
Case 1 (0.5-z)2K=x2(0.5−x)2 0.64 [ Select ] ["taking square root", "direct solving with quadratic equation", "direct solving without quadratic equation", "assuming x is small"]
Case 2 LaTeX: K=\frac{x}{0.5-x}K=x0.5−x 0.80 [ Select ] ["assuming x is small", "taking square root", "direct solving with quadratic equation", "direct solving without quadratic equation"]
Case 3 K= 0.5-rK=x20.5−x 0.86 [ Select ] ["taking square root", "direct solving with quadratic equation", "assuming x is small", "direct solving without quadratic equation"]
Case 4 K= 0.5-rK=x20.5−x 1.3 LaTeX: \times× 10−7 [ Select ] ["assuming x is small", "direct solving with quadratic equation", "taking square root", "direct solving without