For the reaction a + b + c → products, the following initial-rate data were obtained. [a]0 (mol/l) [b]0 (mol/l) [c]0 (mol/l) initial rate (mol/(l ∙ s)) 0.40 0.40 0.20 0.0160 0.20 0.40 0.40 0.0080 0.60 0.10 0.20 0.0015 0.20 0.10 0.20 0.0005 0.20 0.20 0.40 0.0020 what are the reaction orders with respect to a, b, and c, respectively? a. 0, 2, 1 b. 0, 1, 1 c. 1, 2, 0 d. 1, 1, 1 e. 1, 2, 1

e) 1, 2, 1

Explanation:

The given kinetic data is:

A + B + C → Products

     [A]₀     [B]₀    [C]₀       Initial Rate (mol/L.s)

1.   0.4      0.4     0.2      0.0160

2.  0.2      0.4      0.4     0.0080

3.   0.6     0.1       0.2      0.0015

4.   0.2     0.1       0.2      0.0005

5.   0.2     0.2      0.4       0.0020

The rate of the above reaction is :

where x, y and z is the order with respect to A, B and C respectively.

k = rate constant

[A], [B], [C] are the concentrations

In the method of initial rates involves running a given reaction multiple times and measuring the rate in each case. The order with respect to a particular reactant is deduced by keeping the concentrations of the remaining reactants constant and measuring the rates. The ratio of the rates from the two runs gives the order relative to that reactant.

Order w.r.t A : Use trials 3 and 4

Order w.r.t B : Use trials 2 and 5

Order w.r.t C : Use trials 1 and 2

Since the order wrt A and B are known, any of the two trails where the two trials can be used to deduce order wrt C

we know that x = 1 and y = 2, substituting the appropriate values in the above equation gives:

z = 1

Therefore:

Order wrt A = 1

Order wrt B = 2

Order wrt C = 1

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.