BCl3(g) + NH3(g) C13BNH,(S) The reaction represented above is a reversible react

Question

BCl3(g) + NH3(g) C13BNH,(S) The reaction represented above is a reversible reaction. Predict the sign of the entropy change, AS, as the reaction proceeds to the right. Explain your prediction. If the reaction spontaneously proceeds to the right, predict the sign of the enthalpy change, AH. Explain your prediction. The direction in which the reaction spontaneously proceeds changes as the temperature is increased above a specific temperature. Explain. What is she value of the equilibrium constant at the temperature referred to in (c);- that is, the specific temperature at which the direction of the spontaneous reaction changes? Explain.

Explanation / Answer

(a)    S° is negative(–). This is the sign of te entropy change, because high entropy mixture of two kinds of gases forms into a low entropysolid and a pure gas; 3 molecules of gas makes 2 molecules of gas,fewer gas molecules is at a lower entropy.

(b)   G° < 0 ifspontaneous. G° = H° –TS° Since S° isnegatve (–), as T gets larger,–TS° will be­come larger than+145 kJ and the sign of G° be­comespositive (+) and the reaction is non–spon­tanseous.

(c)     When–TS° < +145 kJ,Keq > 1,

          when–TS° = +145 kJ,Keq = 1,

          when–TS° > +145 kJ,Keq < 1, but > 0

(d)     G = 0 at this point,the equation is T = ; this assumes that Hand/or S do not change with tem­perature, whichis not a perfect as­sumption.

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.