One millimole of Ni(NO3)2 dissolved in 250.0 mL of a solution that is 0.500 M  in ammonia. The formation constant of Ni(NH3)62+ is  5.5×108. 0.004 M is the initial concentration of Ni(NO3)2 in the solution.   What is the equilibrium concentration of Ni2+(aq ) in the solution?

Phosphate buffers are important in regulating the pH of intracellular fluids. If the concentration ratio of H2PO4/HPO42 in a sample of intracellular fluid is 1.1: 1, what is the pH of this sample of intracellular fluid? H2PO4(aq)HPO42(aq)+H+(aq)Ka=6.2108

The active ingredient of Pepto-Bismol is the compound bismuth subsalicylate, which undergoes the following dissociation when added to water: C7H5BiO4(s)+H2O(l)C7H4O32(aq)+Bi3+(aq)+OH(aq)K=? If the maximum amount of bismuth subsalicylate that reacts by this reaction is 3.2 1019 mol/L, calculate the equilibrium constant for the preceding reaction.

What are the main equilibria involved in the CO2–Carbonate system and what kind of equilibrium constant is associated with each (K?)?

Calculate the equilibrium concentration of Zn2+(aq) in a solution that is initially 0.150 M Zn(NO3)2 and 0.800 M NH3.   The formation constant for [Zn(NH3)4]2+(aq) is Kf = 2.8 × 109.

One millimole of Ni(NO3)2 dissolves in 240.0 mL of a solution that is 0.500 M  in ammonia.The formation constant of Ni(NH3)62+ is  5.5×108.    What is the initial concentration of Ni(NO3)2 in the solution? What is the equilibrium concentration of Ni2+(aq ) in the solution?

Calculate the silver ion concentration, [Ag'], of a solution prepared by dissolving 1.00 g of AgNO3 and 10.0 g of KCN in sufficient water to make 1.00 L of solution. (Hint: Because k is very large, assume the reaction goes to completion then calculate the [Ag). RAg" (aq) + 2CN (aq) = Ag(CN)2(aq) kr = 1.0 x 1021 42 1g AgNO3 Helpful hint : You will need: AgNO3 = 169.989 1 mol AgNO3 169.98 g AgNO3 mol 5.89 x 103 mol Ag KCN = 65.12 3 mol 19KCN 1 mol KCN 65.12 g KCN 0.154 mol CN-

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Phosgene, COCI,, is a toxic gas used in the manufacture of urethane plastics. The gas dissociates at high temperature. COCI, (2) - CO(9) + Ch (g) At 720.°C, the equilibrium constant K. is 3.63 x 10-. Find the percentage of phosgene that dissociates at this temperature when 4.80 mol of phosgene is placed in a 30.6 L vessel.

The first step in the preparation of magnesium metal is the precipitation of Mg(OH)2 from sea water by the addition of Ca(OH)2. The concentration of Mg2+(aq) in sea water is 5.37 × 10–2 M. Calculate the pH at which [Mg2+] is diminished to 1.0 × 10–5 M by the addition of Ca(OH)2.