Question

The KbKb for methylamine (CH3NH2)(CH3NH2) at 25 ∘C∘C is 4.4×10−44.4×10−4.

Part B. By using the value of KbKb, calculate ΔG∘ΔG∘ for the equilibrium in part A.

Part D. What is the value of ΔGΔG when [H+][H+] = 6.6×10⁻⁹ MM, [CH3NH+3][CH3NH3+] = 2.5×10⁻³ MM, and [CH3NH2][CH3NH2] = 9.70×10⁻² MM?

The value of KaKa for nitrous acid (HNO2)(HNO2) at 25 ∘C∘C is 4.5×10−44.5×10−4. You may want to reference (Pages 833 - 836) Section19.7 while completing this problem.

1. Using the value of KaKa, calculate ΔG∘ΔG∘ for the dissociation of nitrous acid in aqueous solution.

2. What is the value of ΔGΔG when [H+][H+] = 5.6×10−2M5.6×10−2M , [NO−2][NO2−] = 6.2×10−4M6.2×10−4M and [HNO2][HNO2] = 0.21 MM ?

Consider the decomposition of barium carbonate: BaCO3(s)←→BaO(s)+CO2(g)

1. Using data from Appendix C in the textbook, calculate the equilibrium pressure of CO2CO2 at 1250 KK .

Answer 1

Anster) We know that the relation between sa and ky is given by the formula, sh = - RT anko .... where, saº e standard gibb's free energy R = Univers al gas constant = 8.314 Ji meidki T = Temperature = 25°C = (25+273) K = 298% Ko = Bae dissociation constant = 4.4x10 : Now putting the above values in equation 1 we get a shº - - 8.314 J. moh's x 298 Win (4.4x104) is sh = - 8.314 x 298*(-7.728) J.mor . .: A = 19146.6 J, meh! Bioa = 19.1466 kJiment ( 1J = 103kJ) (Answers parto. The dissociation of CH₃NH2 is given by : - H2O + CH3 MHz Ž CH₃NHO + Ono : Now the reaction duotient o is given by, A = [CH3 rig] [OMO] I we know [HH] = 6.6x100 M [CHzr H2] - PH = -log 47 • 2.5*10° x 1.513x106 E-log (6.6x109) pH = 8.18 9.70x10² PH & pot = 14 iso = 3.899 xlos POH = 14-DH = 14 -8.18 We know or - log [olt sh=sho+RT lnd ... 1 = 5+82 | [ON] = 175.82 = (-813 x109)M here, sh = 1914616 J. men R = 8.314 J. moll kl T = 25°c = (25+273) K = 298* B = 3.899 x 108 htt CH3NH2 is given by :-

Now putting the above values in equation @ we get 1a = 1914616 J. moi' +8.314 Jimon'. K7 x 298 x In (3.899x109) a, sh = 19146,6 J.mai't 8.314 J. maí' x 2988(-17.059) a, sh = 19146.6 J.mai 422 64.9 J.most Fish = - 23118.3 J, mort ilohs - 231183 kl. meil ( 1J=103 kJ) JO10 kJ) : The value of sh - 23:1183 KJ.mail (Andrier)