Calculate and determine.

Question

Nitogen dioxide, NO2​, is a red-brown gas that is considered an air pollutant. When heated, nitogen dioxide gas decomposes into nitrogen monoxide and oxygen gas, according to the following reaction. 

2NO2​( g)⇌2NO(g)+O2​( g) 

A sample of nitrogen dioxide in a sealed vessel was heated to 575 K, and the total pressure in the vessel was measured to be 0.0980 atm before any reaction had occured. The total pressure in the vessel was monitored over time during the reaction, giving the following data.

Time (s) Total pressure (atm)

0 0.0980

39 0.1310

53 0.1341

83 0.1379

What is the rate law for the decomposition reaction?

A. rate =kPNO2​​PO2​​ 

B. rate =kPNO2​​ 

C. rate =kPNO2​2​ 

D. rate =k​ 

Calculate the rate constant for the reaction. Determine the units on the rate constant based on the order of the reaction.

k= ???

units: ???

Determine the total pressure in the reaction vessel after 316 s. 

Ptotal ​= ??? atm 

Answer 1

Assume 2nd order in P_NO2

The integrated rate equation (of dP_NO2 = -kP_NO2²) = 1/P_NO2 - 1/P_NO2,0 = kt

You need to connect P_Tot to P_NO2: P_T = P_NO2 + 3/2(P_NO2 - P_NO2,0)

Solve for P_NO2 = 3P_NO2,0 - 2P_T

Substitute the 2nd data point into the equation with the P_T given: I get .5396 1/(s-atm)

You can check other points. (Officially, you should graph 1/P with t and find best fit slope. to find k.)

Use equation to solve for P_NO2 and, then solve for P_T