Problem 22 - Chemistry: The Central Science

Question

Would you expect the substance \(\mathrm{CFBr}_{3}\) to be effective in depleting the ozone layer, assuming that it is present in the stratosphere? Explain.

Step-by-Step Solution

Answer

Yes, \(\mathrm{CFBr}_{3}\) would be effective in depleting the ozone layer if present in the stratosphere, as it contains bromine atoms, which can be released when exposed to UV radiation. Bromine is even more effective in depleting ozone than chlorine, making the substance a potential ozone depleter.

Step 1: Identify the composition of the substance

The given substance is \(\mathrm{CFBr}_{3}\), which is composed of one carbon atom, one fluorine atom, and three bromine atoms. This substance is similar to chlorofluorocarbons (CFCs), which are known ozone depleters, but instead of chlorine atoms, it has bromine atoms.

Step 2: Consider the reactivity of the substance in the stratosphere

In the stratosphere, substances like CFCs are broken down by UV radiation, releasing chlorine atoms that participate in the ozone depletion process. Similarly, we'll consider whether \(\mathrm{CFBr}_{3}\) can release bromine atoms when exposed to UV radiation in the stratosphere. Bromine atoms also play a role in the ozone depletion process, so if the substance can release them, it would be effective in depleting the ozone layer.

Step 3: Compare the effectiveness of bromine in ozone depletion

Both bromine and chlorine atoms can react with ozone, and bromine is known to be even more effective in depleting ozone than chlorine. This is because one bromine atom is about 60 times more effective at destroying ozone molecules than one chlorine atom.

Step 4: Evaluate the effectiveness of \(\mathrm{CFBr}_{3}\) in depleting the ozone layer

Considering that \(\mathrm{CFBr}_{3}\) contains bromine atoms, which are more effective at destroying ozone molecules than chlorine atoms, and given that it can release bromine atoms when exposed to UV radiation in the stratosphere, we can conclude that \(\mathrm{CFBr}_{3}\) would be effective in depleting the ozone layer if it is present in the stratosphere.