Question 1

Components of Air Mole Fraction Nitrogen 0.781
Oxygen 0.209
Argon 0.010
What is the partial pressure or oxygen (in torr)in the atmosphere when the atmospheric pressure is 755.0 torr?

Accepted Answer

The partial pressure of oxygen can be calculated using its mole fraction and the total atmospheric pressure. The formula is: Partial Pressure = Mole Fraction of Gas × Total Atmospheric Pressure. For oxygen, this is 0.209 × 755.0 torr = 157.695 torr, which rounds to 158 torr.

Question 2

The mole fraction of nitrogen in dry air near sea level is 0.78084, where the molar mass of nitrogen is 28.013. The partial pressure of nitrogen when the total atmospheric pressure (dry air)is 97.5 kPa is ________ kPa.

Accepted Answer

According to Dalton's Law of Partial Pressure, the partial pressure of each gas in a mixture of gases is equal to the total pressure multiplied by the mole fraction of that gas. Therefore, the partial pressure of nitrogen can be calculated as:

partial pressure of nitrogen = mole fraction of nitrogen x total atmospheric pressure
partial pressure of nitrogen = 0.78084 x 97.5 kPa
partial pressure of nitrogen = 76.12 kPa

Therefore, the best choice is C, 77.0 kPa, which is the closest value to the calculated partial pressure of nitrogen.

Question 3

What is the wavelength of a photon with just enough energy to break a C-Cl bond? (The bond energy of the C-Cl bond is 331 kJ/mole.)

Accepted Answer

The answer of What is the wavelength of a photon...

Question 4

The mole fraction of nitrous oxide in dry air near sea level is 0.00000050. The concentration of nitrous oxide is ________ molecules per liter, assuming an atmospheric pressure of 739 torr and a temperature of 29.5 °C.

Accepted Answer

To find the concentration of nitrous oxide molecules per liter, we can use the ideal gas law equation in the form of $PV = nRT$, where $P$ is the pressure, $V$ is the volume, $n$ is the number of moles, $R$ is the ideal gas constant, and $T$ is the temperature in Kelvin. Given the mole fraction of nitrous oxide and the conditions (739 torr and 29.5 °C), we can calculate the number of moles of nitrous oxide in a liter of air and then convert that to molecules using Avogadro's number. The correct calculation leads to a concentration of $1.2 \times 10^{16}$ molecules per liter, taking into account the conversion of temperature to Kelvin, pressure to atmospheres, and using the mole fraction correctly.

Question 5

The concentration of which greenhouse gas has increased steadily over the last few decades?

Accepted Answer

The answer of The concentration of which greenhouse gas has...

Question 6

The sterilizing action of chlorine in water is due to what substance?

Accepted Answer

The sterilizing action of chlorine in water is due to the formation of hypochlorous acid (HClO) and hypochlorite ion (ClO-) when chlorine is added to water. These chemicals are powerful oxidizing agents that can destroy microorganisms and organic matter in the water, making it safe to drink.

Question 7

The concentration of water vapor in a sample of air that has a partial pressure of water of 1.20 torr and a total pressure of air of 695 torr is ________ ppm.

Accepted Answer

The concentration in ppm is calculated by (partial pressure of water vapor / total pressure) × 10^6 = (1.20 / 695) × 10^6 = 1.7 × 10^3 ppm.

Question 8

Components of Air Mole Fraction Nitrogen 0.781
Oxygen 0.209
Argon 0.010
What is the partial pressure or nitrogen (in torr)in the atmosphere when the atmospheric pressure is 760.0 torr?

Accepted Answer

The answer of Components of Air Mole Fraction Nitrogen 0.781
Oxygen...

Question 9

The brown color of photochemical smog over a city is mainly due to ________.

Accepted Answer

The brown color of photochemical smog is mainly due to nitrogen oxides (NOx) and volatile organic compounds (VOCs) reacting with sunlight to produce ozone and other harmful chemicals. Therefore, the correct choice is A) NO₂, which represents nitrogen oxides.

Question 10

A sample of air from a home is found to contain 7.2 ppm of carbon monoxide. This means that if the total pressure is 695 torr, then the partial pressure of CO is ________ torr.

Accepted Answer

ppm means parts per million. So, 7.2 ppm of CO means that there are 7.2 parts of CO for every million parts of air. The total pressure is 695 torr, so the partial pressure of CO is:(7.2 ppm / 1,000,000 ppm) * 695 torr = 5.0 * 10^-3 torr

Question 11

The area of the Earth's atmosphere 50 - 85 km above the surface is called the ________.

Accepted Answer

The mesosphere is the layer of the Earth's atmosphere that is located 50 to 85 km above the Earth's surface, sitting above the stratosphere and below the thermosphere.

Question 12

What is the percentage of freshwater on planet Earth?

Accepted Answer

The answer of What is the percentage of freshwater on...

Question 13

In the world's oceans, the average salinity is about ________ g/kg.

Accepted Answer

The average salinity of the world's oceans is approximately 35 g/kg (or parts per thousand), meaning that for every kilogram of seawater, there are 35 grams of dissolved salts and other minerals. Option A, B, D, and E are incorrect as they are either too low or too high compared to the actual average salinity.

Question 14

The concentration of ozone in a sample of air that has a partial pressure of O₃ of 0.53 torr and a total pressure of air of 695 torr is ________ ppm.

Accepted Answer

The partial pressure of ozone is 0.53 torr and the total pressure of air is 695 torr. Therefore, the concentration of ozone is 0.53/695 * 100 = 0.076 ppm.

Question 15

The "scale" caused by hard water is ________.

Accepted Answer

The "scale" caused by hard water is primarily made up of calcium carbonate, which can accumulate on pipes, appliances, and other surfaces.

Question 16

The concentration of carbon monoxide in a sample of air is 6.0 ppm. There are ________ molecules of CO in 1.00 L of this air at 755 torr and 23 °C.

Accepted Answer

The answer of The concentration of carbon monoxide in a...

Question 17

The mole fraction of krypton in dry air near sea level is 0.00000114 where the molar mass of krypton is 83.80. The concentration of krypton in the atmosphere is ________ ppm.

Accepted Answer

The mole fraction of krypton is equivalent to its concentration in parts per million (ppm) when multiplied by 10^6. Therefore, 0.00000114 × 10^6 = 1.14 ppm.

Question 18

Which of the following is (are)not a typical source of nitric oxide?

Accepted Answer

Livestock emissions are not a typical source of nitric oxide. Nitric oxide is primarily produced through combustion processes, atmospheric electrical discharges, and the combustion of organic matter. Livestock emissions mainly contribute to methane and nitrous oxide, not nitric oxide.

Question 19

The concentration of a gas is 3.18 × 10³ ppm at in a container where its partial pressure is 0.591 torr. The total pressure inside the container must be

Accepted Answer

The answer of The concentration of a gas is 3.18...

Question 20

The partial pressure of a gas in air is 1.87 torr and its concentration is 8.57 × 10³ ppm. The total air pressure is ________ torr.

Accepted Answer

The concentration in ppm is the ratio of the partial pressure to the total pressure. Using the formula: (partial pressure/total pressure) × 10^6 = ppm, we can solve for the total pressure: (1.87/total pressure) × 10^6 = 8.57 × 10^3, which gives a total pressure of approximately 218 torr.

Quiz 18: Chemistry of the Environment

Components of Air Mole Fraction Nitrogen 0.781 Oxygen 0.209 Argon 0.010 What is the partial pressure or oxygen (in torr) in the atmosphere when the atmospheric pressure is 755.0 torr?

The mole fraction of nitrogen in dry air near sea level is 0.78084, where the molar mass of nitrogen is 28.013. The partial pressure of nitrogen when the total atmospheric pressure (dry air) is 97.5 kPa is ________ kPa.

What is the wavelength of a photon with just enough energy to break a C-Cl bond? (The bond energy of the C-Cl bond is 331 kJ/mole.)

The mole fraction of nitrous oxide in dry air near sea level is 0.00000050. The concentration of nitrous oxide is ________ molecules per liter, assuming an atmospheric pressure of 739 torr and a temperature of 29.5 °C.

The concentration of which greenhouse gas has increased steadily over the last few decades?

The sterilizing action of chlorine in water is due to what substance?

The concentration of water vapor in a sample of air that has a partial pressure of water of 1.20 torr and a total pressure of air of 695 torr is ________ ppm.

Components of Air Mole Fraction Nitrogen 0.781 Oxygen 0.209 Argon 0.010 What is the partial pressure or nitrogen (in torr) in the atmosphere when the atmospheric pressure is 760.0 torr?

The brown color of photochemical smog over a city is mainly due to ________.

A sample of air from a home is found to contain 7.2 ppm of carbon monoxide. This means that if the total pressure is 695 torr, then the partial pressure of CO is ________ torr.

The area of the Earth's atmosphere 50 - 85 km above the surface is called the ________.

What is the percentage of freshwater on planet Earth?

In the world's oceans, the average salinity is about ________ g/kg.

The concentration of ozone in a sample of air that has a partial pressure of O₃ of 0.53 torr and a total pressure of air of 695 torr is ________ ppm.

The "scale" caused by hard water is ________.

The concentration of carbon monoxide in a sample of air is 6.0 ppm. There are ________ molecules of CO in 1.00 L of this air at 755 torr and 23 °C.

The mole fraction of krypton in dry air near sea level is 0.00000114 where the molar mass of krypton is 83.80. The concentration of krypton in the atmosphere is ________ ppm.

Which of the following is (are) not a typical source of nitric oxide?

The concentration of a gas is 3.18 × 10³ ppm at in a container where its partial pressure is 0.591 torr. The total pressure inside the container must be

The partial pressure of a gas in air is 1.87 torr and its concentration is 8.57 × 10³ ppm. The total air pressure is ________ torr.

Quiz 18: Chemistry of the Environment

Components of Air Mole Fraction Nitrogen 0.781 Oxygen 0.209 Argon 0.010 What is the partial pressure or oxygen (in torr) in the atmosphere when the atmospheric pressure is 755.0 torr?

The mole fraction of nitrogen in dry air near sea level is 0.78084, where the molar mass of nitrogen is 28.013. The partial pressure of nitrogen when the total atmospheric pressure (dry air) is 97.5 kPa is ________ kPa.

What is the wavelength of a photon with just enough energy to break a C-Cl bond? (The bond energy of the C-Cl bond is 331 kJ/mole.)

The mole fraction of nitrous oxide in dry air near sea level is 0.00000050. The concentration of nitrous oxide is ________ molecules per liter, assuming an atmospheric pressure of 739 torr and a temperature of 29.5 °C.

The concentration of which greenhouse gas has increased steadily over the last few decades?

The sterilizing action of chlorine in water is due to what substance?

The concentration of water vapor in a sample of air that has a partial pressure of water of 1.20 torr and a total pressure of air of 695 torr is ________ ppm.

Components of Air Mole Fraction Nitrogen 0.781 Oxygen 0.209 Argon 0.010 What is the partial pressure or nitrogen (in torr) in the atmosphere when the atmospheric pressure is 760.0 torr?

The brown color of photochemical smog over a city is mainly due to ________.

A sample of air from a home is found to contain 7.2 ppm of carbon monoxide. This means that if the total pressure is 695 torr, then the partial pressure of CO is ________ torr.

The area of the Earth's atmosphere 50 - 85 km above the surface is called the ________.

What is the percentage of freshwater on planet Earth?

In the world's oceans, the average salinity is about ________ g/kg.

The concentration of ozone in a sample of air that has a partial pressure of O3 of 0.53 torr and a total pressure of air of 695 torr is ________ ppm.

The "scale" caused by hard water is ________.

The concentration of carbon monoxide in a sample of air is 6.0 ppm. There are ________ molecules of CO in 1.00 L of this air at 755 torr and 23 °C.

The mole fraction of krypton in dry air near sea level is 0.00000114 where the molar mass of krypton is 83.80. The concentration of krypton in the atmosphere is ________ ppm.

Which of the following is (are) not a typical source of nitric oxide?

The concentration of a gas is 3.18 × 103 ppm at in a container where its partial pressure is 0.591 torr. The total pressure inside the container must be

The partial pressure of a gas in air is 1.87 torr and its concentration is 8.57 × 103 ppm. The total air pressure is ________ torr.

The concentration of ozone in a sample of air that has a partial pressure of O₃ of 0.53 torr and a total pressure of air of 695 torr is ________ ppm.

The concentration of a gas is 3.18 × 10³ ppm at in a container where its partial pressure is 0.591 torr. The total pressure inside the container must be

The partial pressure of a gas in air is 1.87 torr and its concentration is 8.57 × 10³ ppm. The total air pressure is ________ torr.