Chapter 18 CHEMISTRY OF THE ENVIRONMENT Go Figure Clicker Questions Chapter 18 CHEMISTRY OF THE ENVIRONMENT Lynn Mandeltort Auburn University

At what altitude is the atmospheric temperature lowest? About 10 km About 50 km About 85 km About 110 km Answer: c

At what altitude is the atmospheric temperature lowest? About 10 km About 50 km About 85 km About 110 km Answer: c

Why doesn’t the solar spectrum at sea level perfectly match the solar spectrum outside the atmosphere? The altitudes are different. The pressures are different. Solar radiation is partially emitted outside the atmosphere. Solar radiation is partially absorbed in the atmosphere. Answer: d

Why doesn’t the solar spectrum at sea level perfectly match the solar spectrum outside the atmosphere? The altitudes are different. The pressures are different. Solar radiation is partially emitted outside the atmosphere. Solar radiation is partially absorbed in the atmosphere. Answer: d

Estimate the ozone concentration in moles per liter for the peak value in this graph. 8 × 10–12 mol/L 8 × 10–9 mol/L 5 × 10–6 mol/L 5 × 1012 mol/L Answer: b

Estimate the ozone concentration in moles per liter for the peak value in this graph. 8 × 10–12 mol/L 8 × 10–9 mol/L 5 × 10–6 mol/L 5 × 1012 mol/L Answer: b

Why is the pH found in freshwater sources in the Eastern half of the United States dramatically lower than found in the western half? The sources are not sampled as frequently in the Western half. More photochemical sources of acids are present in the Eastern half. More industrial production of SO2 is located in the Eastern half. More SO2 is present by chance. Answer: c

Why is the pH found in freshwater sources in the Eastern half of the United States dramatically lower than found in the western half? The sources are not sampled as frequently in the Western half. More photochemical sources of acids are present in the Eastern half. More industrial production of SO2 is located in the Eastern half. More SO2 is present by chance. Answer: c

What is the major solid product resulting from removal of SO2 from furnace gas? CaO(s) CaSO3(s) CaCO3(s) CO2(s) Answer: b

What is the major solid product resulting from removal of SO2 from furnace gas? CaO(s) CaSO3(s) CaCO3(s) CO2(s) Answer: b

What fraction of the incoming solar radiation is absorbed by Earth’s surface? (168 W/m2)/(342 W/m2)—about half 342 W/m2—nearly all (324 W/m2)/342 W/m2—the majority Answer: a, Keep in mind that the IR radiation absorbed by Earth’s surface is not directly solar radiation.

What fraction of the incoming solar radiation is absorbed by Earth’s surface? (168 W/m2)/(342 W/m2)—about half 342 W/m2—nearly all (324 W/m2)/342 W/m2—the majority Answer: a, Keep in mind that the IR radiation absorbed by Earth’s surface is not directly solar radiation.

What is the source of the slight but steady increase in slope of this curve over time? An increasing amount of CO2 in the atmosphere, probably from combustion of fossil fuels An increasing rate of production of CO2 put into the atmosphere, probably from combustion of fossil fuels An increasing rate of production of CO2 put into the atmosphere, probably from the decreasing number of trees using CO2 in photosynthesis Seasonal changes Answer: b

What is the source of the slight but steady increase in slope of this curve over time? An increasing amount of CO2 in the atmosphere, probably from combustion of fossil fuels An increasing rate of production of CO2 put into the atmosphere, probably from combustion of fossil fuels An increasing rate of production of CO2 put into the atmosphere, probably from the decreasing number of trees using CO2 in photosynthesis Seasonal changes Answer: b

Which processes shown in this figure involve the phase transition H2O(l) H2O(g) Precipitation to land and water Sublimation from land Condensation onto land and water Evaporation from freshwater, seawater, and land Answer: d

Which processes shown in this figure involve the phase transition H2O(l) H2O(g) Precipitation to land and water Sublimation from land Condensation onto land and water Evaporation from freshwater, seawater, and land Answer: d

How would you expect the temperature variation to affect the density of seawater in the range 0 to 100 m depth? The density will increase with increasing depth (decreasing T). The density will decrease with increasing depth (decreasing T). The density will not be related to the depth and temperature. Answer: a

How would you expect the temperature variation to affect the density of seawater in the range 0 to 100 m depth? The density will increase with increasing depth (decreasing T). The density will decrease with increasing depth (decreasing T). The density will not be related to the depth and temperature. Answer: a

What feature of this process is responsible for its being called reverse osmosis? Water crosses the membrane, not ions. Ions cross the membrane, not water. Solute molecules move through the membrane. The solvent of the dilute solution passes through membrane into more concentrated solution. Answer: a

What feature of this process is responsible for its being called reverse osmosis? Water crosses the membrane, not ions. Ions cross the membrane, not water. Solute molecules move through the membrane. The solvent of the dilute solution passes through membrane into more concentrated solution. Answer: a

What is the primary function of the aeration step in water treatment? To cool the water To speed up oxidation of unwanted inorganic components To mix the water with bleach and other chemical treatments To enhance evaporation of organic solvent material Answer: b

What is the primary function of the aeration step in water treatment? To cool the water To speed up oxidation of unwanted inorganic components To mix the water with bleach and other chemical treatments To enhance evaporation of organic solvent material Answer: b