Question

4 4. a) Parts (a) and (b) below are separate independent problems For each of the following, write a balanced net-ionic equation for the acid-base neutralization reaction that occurs (omitting any spectator ions), and determine the value of the equilibrium constant K for the reaction. Be sure to include phases (such as (aq) or ()) in your reactions. The first one is done for you as an example. (8 pts) Example: Solutions of HBr (ag) and KOH (aq) are mixed together. reaction: H+ (aq) OH- (aq)H20 (D) -1.0x 1014 i) Solutions of NH3 (aq) and HCI (aq) are mixed together. reaction: ii) Solutions of HF (aą) and NaCN (aq) are mixed together reaction: For each of the following, circle True or False to indicate if the statement is correct. (2 pts each) i) True False H2PO4" and HPO2 are a conjugate acid/base pair. ii) b) For some reactions in which all reactants and products are in the gas-phase, Kp Ke True False For cach of the following solutions, indicate if the resulting solution will be a buffer or not a buffer by circling the appropriate choice. Each solution is prepared by dissolving the indicated quantities of chemicals in 1.00 liter of water. (1 pt each) (circle your answer) c) i) 0.400 moles HCl and 0.400 moles NaOH:buffer ii) 0.400 moles HCN and 0.200 moles NaOH: buffer i) 0.200 moles HNO3 and 0.400 moles NaCN: buffer iv) 0.400 moles HCl and 0.200 moles NaCN: buffer not a buffer not a buffer not a buffer not a buffer 16 pts)

Answer 1

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