Nitrogen oxides. NO_x (a mixture of NO and NC_2 collectively designated as NO_x)

Question

Nitrogen oxides. NO_x (a mixture of NO and NC_2 collectively designated as NO_x), play an essential role in the production of pollutants found m photochemical smog. The NO_x in the atmosphere is slowly broken down to N_2 and O_2 in a first-order reaction. The average half-life of NO_x in the smokestack emissions in a large city during daylight is 3.9 hours. Starting with 5.20 mg in an experiment, what quantity of NO_x remains after 5.16 hours? Nitrogen oxides. NO_x (a mixture of NO and NO_2 collectively designated as NO_x), play an essential role in the production of pollutants found in photochemical smog. The NO_x in the atmosphere is slowly broken down to N_2 and O_2 in a first-order reaction. The average half-life of NO_x in the smokestack emissions in a large city during daylight is 3.9 hours. How many hours of daylight must have elapsed to decrease 5.20 mg of NO_x to 1.04 Times 10 Times 10^-5 mg?

Explanation / Answer

The reaction is first order.

So, rate constant, k = 0.693/t1/2 = (0.693/3.9) hour-1

The first order rate constant is: k= (1/t) ln (a/a-x).......equation(1)

a. From equation 1 we can write,

(0.693/3.9) hour-1 = (1/5.16 hour) ln (100/a-x)

or, a-x = 39.97 %

So quantity of NOx remains after 5.16 hours = a-x = 39.97% of 5.2 mg = 2.078 mg

b. From equation 1 we can write,

(0.693/3.9) hour-1 = (1/t) ln (5.2/1.04*10-5 )

or, t = 73.85 hours

Related Questions

Navigate

• Browse (All)
• Browse N
• Subjects

---

---

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