Skip to main content
Ch.18 - Chemistry of the Environment
Brown - Chemistry: The Central Science 14th Edition
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232당신이 사용하는 게 아니라요?교과서 변경
모든 교과서Brown 14th EditionCh.18 - Chemistry of the Environment문제 77
18장, 문제 77

As of the writing of this text, EPA standards limit atmospheric ozone levels in urban environments to 84 ppb. How many moles of ozone would there be in the air above Los Angeles County (area about 4000 square miles; consider a height of 100 m above the ground) if ozone was at this concentration?

검증된 단계별 안내
1
Convert the area of Los Angeles County from square miles to square meters. Use the conversion factor: 1 square mile = 2.59 x 10^6 square meters.
Calculate the volume of the air column above Los Angeles County by multiplying the area in square meters by the height of the column (100 meters).
Convert the ozone concentration from parts per billion (ppb) to a molar concentration. Assume standard conditions (1 atm, 298 K) and use the ideal gas law to find the molar volume of air.
Calculate the total number of moles of air in the volume calculated in step 2 using the molar volume from step 3.
Determine the number of moles of ozone by multiplying the total moles of air by the concentration of ozone in moles per mole of air (from step 3).

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Molar Volume of a Gas

At standard temperature and pressure (STP), one mole of an ideal gas occupies approximately 22.4 liters. This concept is crucial for converting between moles and volume, especially when dealing with gases like ozone in atmospheric calculations.
추천 영상:
가이드 코스
00:51
The Ideal Gas Law: Molar Mass

Concentration Units

Concentration can be expressed in various units, including parts per billion (ppb). In this context, 84 ppb means there are 84 molecules of ozone per billion molecules of air, which is essential for determining the total amount of ozone in a given volume of air.
추천 영상:
가이드 코스
02:13
SI Units

Volume Calculation

To find the total volume of air above a specified area, one must calculate the volume using the area and height. For Los Angeles County, the volume can be calculated by multiplying the area (in square meters) by the height (in meters), which is necessary for determining the total moles of ozone present.
추천 영상:
가이드 코스
02:35
Constant-Volume Calorimetry
관련 실천
교과서 질문

(b) Will Mg(OH)2 precipitate when 4.0 g of Na2CO3 is added to 1.00 L of a solution containing 125 ppm of Mg2+?

367
views
교과서 질문

(a) The EPA threshold for acceptable levels of lead ions in water is 615 ppb. What is the molarity of an aqueous solution with a concentration of 15 ppb?

1
views
교과서 질문

In 1986 an electrical power plant in Taylorsville, Georgia, burned 8,376,726 tons of coal, a national record at that time. (b) If 55% of the SO2 could be removed by reaction with powdered CaO to form CaSO3, how many tons of CaSO3 would be produced?

1
views
교과서 질문

(b) Concentrations of lead in the bloodstream are often quoted in units of μg/dL. Averaged over the entire country, the mean concentration of lead in the blood was measured to be 1.6 μg/dL in 2008. Express this concentration in ppb.

378
views
교과서 질문

In 1986 an electrical power plant in Taylorsville, Georgia, burned 8,376,726 tons of coal, a national record at that time. (a) Assuming that the coal was 83% carbon and 2.5% sulfur and that combustion was complete, calculate the number of tons of carbon dioxide and sulfur dioxide produced by the plant during the year.

1470
views
교과서 질문

The estimated average concentration of NO2 in air in the United States in 2006 was 0.016 ppm. (a) Calculate the partial pressure of the NO2 in a sample of this air when the atmospheric pressure is 755 torr (99.1 kPa).

504
views