The ionization constant for NH4+ is K = 5.8 x 10-10 at 25°C. It is in a reversible equilibrium with ammonia and H+. NH4+ --> NH3 + H+ where, H+ + NH3 --> NH4* with a k₁ = 4.000 x 1010 M-1 S-1 A temperature jump from 20°C to 25°C is made on a 0.1 M NH4Cl solution at pH 6. Calculate the relaxation time in microseconds for the reaction, assuming that the mechanism is given by the ionization equation shown. Assume that the pH is buffered.

8-112 Consider an initial 0.040 M hypobromous acid (HOBr) solution at a certain temperature. At equilibrium after partial dissociation, its pH is found to be 5.05. What is the acid ionization constant, Ka, for hypobromous acid at this temperature?

Consider the weak bases below and their Kp values: NH3 Ky = 1.8 x 10-5 C2H5NH2 Kp = 5.6 x 10-4 C5H5N Kp = 1.7 x 10-9 Arrange the conjugate acids of these weak bases in order of increasing acid strength. O CsH;NH< NH,*< C2H5NH3* C2H5NH;*= NH,= C5H5NH* C2H5NH3*< NH4*< C5H5NH* O NH,*< C,H5NH;*

COHSOH(ag) + H2On + CeHsO (aq) + H3O*(a9) Ka= 1.12 x 10-10 (a) Phenol is a weak acid that partially dissociates in water according to the equation above. Write the equilibrium-constant expression for the dissociation of the acid in water. (b) What is the pH of a 0.75 M CaHsOH(ag) solution? (C) For a certain reaction involving CaHsOH(ag) to proceed at a significant rate, the phenol must be primarily in its deprotonated form, C3H5O (eg). In order to ensure that the CsHsOH(aq) is deprotonated, the reaction must be conducted in a buffered solution. On the number scale below, circle each pH for which more than 50 percent of the phenol molecules are in the deprotonated form (CoHsO (aq). Justify your answer. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Justification: (d) CeHsOH(ag) reacts with NaOH(ag). Write a net ionic equation representing this reaction (aka: invasion equation). (e) What is the pH of the resulting solution when 30 mL of 0.40 M CSH5OH(aq) is added to 25 mL of 0.60 M NAOH. Show all work…