The pKa of NH4+ is 9.25 at 25°C. The rate constant at 25°C for the reaction of NH4+ and OH− to form aqueous NH3 is 4.0 ✕ 1010 dm3 mol−1 s−1. Calculate the rate constant for proton transfer to NH3 (Units of s-1).
pKa ofNH4+
NH4+ + H2O <--> NH3 + H3O+
Ka = [NH3][H3O+]/[NH4+]
Ka = 10^-pKa = 10^-9.25
Let "K" be the rate constant for forward reaction and reverse(2nd order) reaction
k = 4*10^10 1/(Ms)
Calculte Rate constant for H+ transfer
K = [NH4+][OH-]/([NH3][H2O])
recall that
Kw = Ka*Kb
Kb = Kw/Ka = (10^-14)/(10^-9.25) = 1.78*10^-5
Then
for Rate constant
Kb = K/K'
K = Kb*K´
K = (1.78*10^-5)(4*10^10)
K = 7.12*10^5 1/s
The pKa of NH4+ is 9.25 at 25°C. The rate constant at 25°C for the reaction...
The pKa of NH4+ is 9.25 at 25°C. The rate constant at 25°C for the reaction of NH4+ and OH− to form aqueous NH3 is 4.0 ✕ 1010 dm3 mol−1 s−1. Calculate the rate constant for proton transfer to NH3. s−1 What relaxation time would be observed if a temperature jump were applied to a solution of 0.31 mol dm−3 NH3(aq) at 25°C?
please answer the relaxation time question correctly with the
correct units asked in the question. thank you
The pKa of NH4+ is 9.25 at 25°C. The rate constant at 25°C for the reaction of NH4+ and OH- to form aqueous NH3 is 4.0x1010 dm3 mol-1 s- Calculate the rate constant for proton transfer to NH3. What relaxation time would be observed if a temperature jump were applied to a solution of 0.13 mol dm-3 NH3(aq) at 25°C? 0.027 ns
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