Caps Lock 2C. The following mechanism has been 5&6The following questions refer
ID: 1027510 • Letter: C
Question
Caps Lock 2C. The following mechanism has been 5&6The following questions refer to the reaction 2A+B Step 1 (very slow) step 2 (slow) A2 + B2 R + C Which step is rate determining? Both steps B. Step Which species is an intermediate? C Step . Not possible to determine from information A. A B. B C. R D.CE. No intermediates present -The rate constant for a reaction is 1.4 × 10 s-, at 714 K and 4.1x 10',-1 at 920 K. what is the activation energy? A. 12.0 kJ/mol B. 28 kJmol C. 540 kJ/mol D. 3400 kJ/mol E. 0.0120 kJ/mol -Apply the law ofmass action to determine the equilibrium expression for 8.Explanation / Answer
5. 2A2 + B2 ------------> 2C
step 1 ( very slow) A2 + B2 --------> R + C
step 2 ( slow) A2 + R ---------> C
Rate of reaction depends upon the slow step . It is called rate determining step.
D. not possible to determine from information
6. R is an intermediate
C. R
7.
log(K2/K1) = Ea/2.303R [1/T1- 1/T2]
log(4.1*10^-2/1.4*10^-2) = Ea/2.303*8.314 [ 1/714 - 1/920]
0.4666 = Ea(0.0014-0.0011)/19.147
Ea = 0.4666*19.147/0.0003 = 28000J = 28KJ/mole
B. 28KJ/mole
8. 2NO2Cl(aq) -------------> 2NO2(aq) + Cl2(aq)
K = [NO2]^2[Cl2]/[NO2Cl]^2
D.K = [NO2]^2[Cl2]/[NO2Cl]^2