You are working with an artist who has been commissioned to make a sculpture for a big city in the eastern United States. The artist is wondering what material to use to make her sculpture because she has heard that acid rain in the eastern United States might destroy it over time. You take samples of granite, marble, bronze, and other materials, and place them outdoors for a long time in the big city. You periodically examine the appearance and measure the mass of the samples. (b) What chemical process (or processes) is (are) the most likely responsible for any observed changes in the materials? [Section 18.2]

Video transcript

Hey everyone, we're told that several materials are available to be used for sculpture. They're placed outside where they are exposed to the heat of the sun and acid rain. Their mass and appearance were recorded from time to time. Which of the following statements could be used as a basis to select the best material to be used for the sculpture. First. Before we look at our answer choices, let's go ahead and think about what we know. We want to select the best materials for the sculpture that is exposed to the heat of the sun and acid rain. Hearing that the first thing that comes to my mind is erosion. And we want to avoid erosion in order for our sculpture to be maintained for a long period of time. And we know that the two main chemical processes that lead to erosion, our reactions with acid rain and corrosion or air oxidation. Now looking at our answer choices, we see that this matches answer choice A And we want the material to not react with acid, since we know that it is going to be exposed to acid rain. And we want the material to not undergo air oxidation because both of these will lead to erosion. So our answer here is going to be answer choice. A Looking at our other answer choices. We have be the material state firmed but lighter. Now this answer choice wouldn't be used as a basis for selecting our best material for this sculpture because it doesn't necessarily protect us from our weather conditions that we are given. And the same goes for answer choice E, which states the material becomes shinier and heavier. Lastly, looking at answer choice D, the material corroded and eroded. This answer choice is not our answer, because this is exactly what we want to avoid. So we wouldn't want to use corroded and eroded material as our basis for our sculpture. So I hope that made sense and let us know if you have any questions.