Phosgene is a toxic gas prepared by the reaction of carbon monoxide with chlorin

Question

Phosgene is a toxic gas prepared by the reaction of carbon monoxide with chlorine.

CO(g) + Cl2(g)   COCl2(g)

These data were obtained in a kinetic study of its formation.

(a) Write the rate law for the formation of phosgene. (Rate equations take the general form 'rate = k . [A] . [B]'.)

Experiment   Initial Rate
(mol/L·s) Initial [CO]
(mol/L) Initial [Cl2]
(mol/L) 1   1.29 10-29        1.00       0.100 2   1.33 10-30        0.100       0.100 3   1.30 10-29        0.100       1.00 4   1.32 10-31        0.100       0.0100

Explanation / Answer

Answer – We are given, rate of formation and concentrations of both reactant

First we need to calculate the order of reaction, let assume order with respect CO is m and with respect to Cl2 is n

So overall rate of reaction is -

Rate = k [CO]m [Cl2]n

and rate law are as follow for each experiment -

Rate1 = k [CO]1m [Cl2]1n

Rate2 = k [CO]2m [Cl2]2n

Rate 3 = k [CO]3m [Cl2]3n

Rate 4 = k [CO]4m [Cl2]4n

Now first we need to calculate order of CO

So,

Rate2/ Rate1 = k [CO]2m [Cl2]2n / k [CO]1m [Cl2]1n

1.33*10-30 / 1.29*10-29 = ((0.100)m /(1.00)m) * (0.100)n / (0.100)n

0.103 = (0.100)m

So, m = 1

So order with respect to CO is first order

Now order of Cl2

Rate4/Rate3 = k [CO]4m [Cl2]4n / k [CO]3m [Cl2]3n

1.32*10-31 / 1.30*10-29 = (0.100)m /(0.100)m) * (0.010)n / (1.00)n

0.0101 = (0.01)n

So, n = 1

So order with respect Cl2 is first order

So overall order = 1 + 1 = 2

So rate law,

Rate = k [CO] [Cl2]

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---