Which one of the following statements about catalysts is true? (a) Addition of a

Question

Which one of the following statements about catalysts is true? (a) Addition of a catalyst does not affect the energy change between reactants and products. (b) Catalysts work by increasing the kinetic energy of the reactants in the reaction. (c) Addition of a catalyst decreases the number of effective collisions per second. (d) Catalysts increase the activation energy of the molecules allowing them to react faster. (e) Homogeneous catalysts exist in a different phase from the reactants. (x) The activation energy for a certain reaction is 262 kJ middot mol^-1. At 600 K the rate constant is 6.07 times 10^-8 s^-1. What is the rate constant at 800 K in units of s^-1? (a) 8.09 times 10^-8 (b) 7.97 times 10^-7 (c) 5.85 times 10^-8 (d) 1.20 times 10^-13 (e) 3.06 times 10^-2

Explanation / Answer

ix) a

because the product formed will be same ...with or wothout catalyst...hence the delta Hf..(delta H react - delta H prodt)

x) k = A e-(Ea/RT)

taking ln on both sides

ln(k2/k1) = Ea/R ((1/T1)-(1/T2))

ln(k2/ 6.07 X10-8) = 262 X1000 X ((1/600)-(1/800))

or

ln(k2/ 6.07 X10-8) = 13.13

k2/ 6.07 X10-8 = 504066.921

or k2= 3.06 X10-2

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

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