Skip to main content
Pearson+ LogoPearson+ Logo
Ch.18 - Chemistry of the Environment
Back
Previous problem
Next problem
All textbooksBrown 15th EditionCh.18 - Chemistry of the EnvironmentProblem 17b

Chapter 18, Problem 17b

(b) Use the energy requirements of these two pro- cesses to explain why photodissociation of oxygen is more important than photoionization of oxygen at altitudes below about 90 km.

Verified Solution
Video duration:
2m
This video solution was recommended by our tutors as helpful for the problem above.
520
views
Was this helpful?

Video transcript

Hi everyone for this problem, We're told at altitudes below 80 km. Photo ionization of oxygen becomes more important than photo dissociation of oxygen is this statement true or false. So we want to know whether it's true or false if photo ionization is more important than photo dissociation at altitudes below 80 km. So the first thing we want to do is to compare the two. So let's start off by talking about photo dissociation. Okay, photo dissociation is bond breaking, and this requires killing joules per mole of energy. On the other hand, photo ionization, this is ejecting an electron and this requires 205 kg joules per mole of energy. So, as we can see, photo dissociation has a lower energy than photo ionization. Okay, so with energy and wavelength they have an inverse relationship. Okay, so this should say lower energy. So because photo dissociation has lower energy, it means it's going to require longer wavelengths and I'm going to put a lambda here for wavelength. On the other hand, photo ionization because it has higher energy, it's going to require shorter wavelengths. Okay, so let's consider our altitude given here At lower elevations, shorter wavelengths have already been absorbed. So longer wavelengths can pass through. So below 80 km is going to require longer wavelengths. So, because of this photo dissociation is going to dominate. Okay, so that is going to make this statement false. So we're gonna go ahead and write false because photo dissociation is what's going to dominate and that is going to be the answer to the statement. The statement is false. Okay, Because photo dissociation dominates. That's the end of this problem. I hope this was helpful.
Previous problemNext problem
Related Practice
Textbook Question

Air pollution in the Mexico City metropolitan area is among the worst in the world. The concentration of ozone in Mexico City has been measured at 441 ppb (0.441 ppm). Mexico City sits at an altitude of 7400 feet, which means its atmospheric pressure is only 0.67 atm. (b) How many ozone molecules are in 1.0 L of air in Mexico City? Assume T = 25 °C.

1175
views
Textbook Question

From the data in Table 18.1, calculate the partial pressures of carbon dioxide and argon when the total atmospheric pressure is 1.05 bar.

1205
views
Textbook Question

The dissociation energy of a carbon-bromine bond is typically about 276 kJ/mol. (a) What is the maximum wavelength of photons that can cause C-Br bond dissociation?

1345
views
Textbook Question

The wavelength at which the O2 molecule most strongly absorbs light is approximately 145 nm. (a) In which region of the electromagnetic spectrum does this light fall?

1827
views
Textbook Question

The ultraviolet spectrum can be divided into three regions based on wavelength: UV-A (315–400 nm), UV-B (280–315 nm), and UV-C (100–280 nm). (b) In the absence of ozone, which of these three regions, if any, are absorbed by the atmo- sphere?

1344
views
Textbook Question

Which of the following reactions in the stratosphere cause an increase in temperature there? (a) O(g) + O2(g) → O3+(g) (b) O3*(g) + M(g) → O3(g) + M*(g) (c) O2(g) + hv → 2 O(g) (d) O(g) + N2(g) → NO(g) + N(g) (e) All of the above

515
views