Question

A solution of 400.0 mL of 0.050M Fe(NO3)2 are mixed with 0.8 L of 1.8 MK2X, where X represents an unknown ion, acts as a ligand to form a complex ion with the Fe2+ ion with a coordination number of two. a) Calculate the equilibrium constant for the following formation. Fe2+ + 2x2-= [Fe(X)2]2- Fe2+ + X2- = Fex K1 = 6.46 x 103 [Fe(X)222-2 FeX + X2 K2 = 2.34 x 10-2 K= 2.76 * 10% (Correct to 3 sig. fig) b) Hence, calculate the equilibrium concentration of the Fe2+ ion. [Select] * 10-8M [Select] 8.35 4.44 2.41 6.33 3.63 7.45

Can you help me with b?

Thank you.

Answer 1

Ji Total volume - 4oomL t 0.8 x 1000 L mal looo 1200 m2 Vrstal = 1022 [Fe(NO3)2] = 0.05% 400 L 102 L [Feay! [Fe (N03),J = 0.017 M [x3] = [kxJ'= 1.8 x 0-8 lo 2 [x2] = 102 Fe2+ + 2x2 - K [Fe (x2) I 0.017 12 o C -2 -2X E 0.017-X 1-2-are 2.76X16 = K = [Fe (x)] = 3C [Fe2+3 [x3072 2.76x15 7 x 6-017-2)(4x2+1-44–4189) on solving x = 0001699994607 [Fe 2+] = 0.017 - x = 0 [Feet] = 5-393x108) 6-017-2) (1-2-20,3 393 x 10