AP Environmental Science Unit 7 Practice Test: Atmospheric Pollution

The correct answer is (A). Secondary pollutants are defined as pollutants that form as a result of atmospheric reactions involving a primary pollutant(s). Ozone is an example of a secondary pollutant because it results from a chemical reaction between two primary pollutants: nitrogen oxide and volatile organic compounds, in the presence of sunlight. The other answer choices are all examples of primary pollutants.

The correct answer is (B). The Montreal Protocol was a global effort designed to regulate substances that diminish the ozone layer. This has been a successful international agreement, and the ozone hole over Antarctica is slowly recovering. It is projected that the ozone layer will return to 1980 levels sometime between 2050 and 2070.

The correct answer is (C). Recycling processes are broadly classified into two categories: open-loop recycling and closed-loop recycling. With closed-loop recycling, end-of-life products are recycled into the same product. An example of closed-loop recycling is a used aluminum can that is recycled into a new aluminum can. Open-loop recycling is the process where material from one or more products is made into a new product, usually involving a change in the material itself. For instance, recycled plastic packaging might be used to make outdoor furniture.

The correct answer is (A). Point sources of pollution come from a distinct point of entry into a water body. Nonpoint sources come from more diffuse, large-spread areas of residential, agricultural, or urban areas.

The correct answer is (B). Lead is a heavy metal and a serious health threat. It is rarely found in natural water sources. Its main source is lead-lined pipes of older homes, brass fittings containing lead, and materials, such as solder, that are used to fasten pipes together.

The correct answer is (B). Carbon monoxide is released from the incomplete the combustion of any kind. Carbon monoxide bonds to hemoglobin, interfering with oxygen transport in the bloodstream. It causes headaches in low concentrations and death in higher concentrations. Sulfur dioxide is a byproduct of combustion of fuels that contain sulfur, including coal, oil and gasoline. It is a respiratory irritant, harmful to plants, and contributes to acid precipitation. Carbon dioxide is a byproduct of burning fossil fuels, affecting climates and increasing greenhouse gasses. Ozone is a secondary pollutant formed by the combination of sunlight, water, oxygen, VOCs and NOx.

The correct answer is (A). Most amphibians cannot survive in water that has a pH less than 6.0. Amphibians are affected by acidity because they absorb water through their skin.

The correct answer is (C). Radon is a radioactive gas that results from the decay of uranium. It seeps into homes through cracks in the foundation or soil. Human exposure to radon can cause lung cancer. Asbestos is a material used in insulation and causes respiratory diseases and lung cancer. Carbon monoxide, in addition to being an outdoor air pollutant, can also be an indoor air pollutant. Carbon monoxide binds with hemoglobin more efficiently than oxygen and reduces the amount of oxygen in the bloodstream. VOCs, or volatile organic compounds, are used in building materials, furniture, and other home products and are suspected to be carcinogenic. Mercury is a neurotoxin, which can damage the brain, kidneys, liver, and immune system.

The correct answer is (D). Since lead was removed from gasoline, there has been a significant decline in lead found in the atmosphere.

The correct answer is (C). To change ppm (parts per million) to a percentage, simply move the decimal place four places to the left and add a % sign.