Question

The equilibrium constant for the equation HNO3(aq) + H2O(l) = H, 0+ (aq) + NO2 (aq) is Kg = 5.6 x 10-4 M at 25.0 °C. Calculate the value of AGixn at 25.0 °C for nitrous acid when [NO2] = [H3O+] = [HNO2] = 1.00 M. AGixn = kJ/mol Will the acid spontaneously dissociate under these conditions? O no O yes Calculate the value of AGrxn for nitrous acid when [NO, ] = [H,O+] = 7.13 x 10- M and [HNO, ] = 1.046 M. AGrxn = kJ/mol Will the acid spontaneously dissociate under these conditions? no O yes

Answer 1

Ah- oh ha Bho+kt In Toh Tavi - t When then to vie other oh for the reaction, D.A,+ W,A2 = ;Az%A4 Vi are the storehiometric dselricient or the reactants. Dh_A6 = - RTlock So, here in the first case, tt aii - [1230t] [Noz] HNO₃(aq) + 404) H30734) + Noz (aer, [+Nor] here activitas lai is replaced by the concentration (ei). of the reactants due to dilute solution. Dhren - Rolnika = -8314 (25+273) In (5.610-4) Imort = 18.55 x103 kJ/mol - 18.55 ki/mol vou, Criteria of spontanity of a reaction is obz<o But here AG) so, the reaction is not spontaneous The aid will not spontaneously dissociate under this condition.

Mati - ANO, A 130t * [NO2] = [2.30 t] = 7 8 x 18 5M and [HINO2] = 1.016 M. ! by replacing with concentation by replacing i CANOR term, * [No, [10] CANon] 7:13x10-5 x 7-13x10-5 M o n te 1.046 SL = 4.86610-9 M ml Inox Shrean toho + RT in (1.86+159) g) . TR-8 319 3 kimeri = 18.55 x103 — 47.42x103 T =35+2778) = - 28.87X163 2.298 K Ohram = -28.87X103 J/mol = -28,87 kJ/mol al resto hot bosta lorean - 4 i Dharan 10 days and worst boriste noot of i. The reaction is spontaneous linder these for and condition. Il must hbrootoo lolex old biting sundon troosami otsib doktor 1 lms stad

Here the activity of the reactants are replaced by the concentration term assuming the solution is dilute.