Deck 21: Environmental Chemistry Earths Environment,energy,and Sustainability

Question 1

Helium and argon are added continuously to the atmosphere.What is the primary source of these gases?

A) the solar wind
B) mining operations
C) burning of fossil fuels
D) radioactive decay
E) volcanic eruptions

Answer 1

radioactive decay

Question 2

Which water pollutant can lead to an increased occurrence in skin lesions and skin cancer when ingested at unsafe (toxic)levels?

A) arsenic
B) copper
C) mercury
D) fluoride
E) lead

Answer 2

arsenic

Question 3

Which water pollutant is responsible for algal blooms?

A) arsenic
B) phosphates
C) mercury
D) fluoride
E) trihalomethanes

Answer 3

phosphates

Question 4

The minimum wavelength of light required to decompose a single ozone molecule is 320.nm.Calculate the minimum energy required to decompose 1.00 mole of ozone.(h = 6.626 $\times$ 10^-34 J.s; c = 3.00 $\times$ 10⁸ m/s; 1 nm = 10^-9 m; 1mol = 6.022 $\times$ 10²³)

A) 6.21 $\times$ 10^-19 kJ/mol
B) 120 kJ/mol
C) 0.374 kJ/mol
D) 374 kJ/mol
E) 0.00267 kJ/mol

Question 5

Which of the following is not responsible for the formation and/or release of methane into the atmosphere?

A) aerobic bacteria
B) cows
C) landfills
D) mining
E) termites

Question 6

Which of the following is the main form of nitrogen absorbed by plants?

A) NH₃
B) NH₄⁺
C) NO₃^-
D) N₂
E) NO₂

Question 7

Which gas has the highest concentration in the Earth's atmosphere?

A) N₂
B) O₂
C) Ar
D) CO₂
E) O₃

Question 8

The conversion (fixation)of N₂ to its compounds is accomplished by a number of natural and artificial processes.Which of the following account for around 50% (the highest amount)of worldwide conversion of nitrogen to its compounds?

A) burning fossil fuels
B) lightening
C) biological processes
D) fertilizer production
E) volcanic eruptions

Question 9

All of the following are used by various cities and municipalities to disinfect water except ___.

A) Cl₂
B) NaOCl
C) O₃
D) UV-light
E) O₂

Question 10

Which of the following water disinfectants persist in water pipes even after the initial disinfection process?

A) Cl₂
B) NaOCl
C) O₃
D) A and B
E) A,B,and C

Question 11

The mechanism of the chlorine atom catalyzed decomposition of ozone is as follows.
O₃ + $\to$ Cl -ClO + O₂
-ClO + -O $\to$ -Cl + O₂
O₃ + UV light $\to$ -O + O₂
Identify any intermediates in the mechanism.

A) O₃
B) (-Cl)
C) (-ClO)
D) O₂
E) (-O) and (-Cl)

Question 12

The largest $\underline{\text{ renewable }}$ source of electricity production in the United States is from ___.

A) wind
B) hydroelectricity
C) solar
D) geothermal
E) biomass

Question 13

What is the correct name for NO₃^-?

A) nitric oxide
B) nitrite
C) nitrogen trioxide
D) nitrous oxide
E) nitrate

Question 14

What compound was used by the ancient Egyptians and is still used today in the removal of visible impurities (cloudiness)in water?

A) sand (SiO₂)
B) aluminum(III)hydroxide (Al(OH)₃)
C) slaked lime (Ca(OH)₂)
D) alum (KAl(SO₄)₂)
E) chlorine (Cl₂)

Question 15

The majority of electricity generated in the United States is produced from ___.

A) wind and solar
B) moving water
C) nuclear fission
D) natural gas
E) coal

Question 16

Which ion occurs in the highest concentration in seawater?

A) Cl^-
B) Na⁺
C) HCO₃^-CO₃^2-
D) Mg²⁺
E) Ca²⁺

Question 17

What is the most abundant nitrogen oxide in the atmosphere?

A) NO
B) NO₂
C) N₂O
D) NO₃^-
E) NO₂^-

Question 18

What is the electron geometry around the central oxygen in O₃?

A) linear
B) bent
C) trigonal planar
D) tetrahedral
E) trigonal bipyramidal

Question 19

Which of the following is $\underline{\text{ not }}$ considered a renewable source of energy?

A) solar energy
B) hydroelectric power
C) nuclear fission
D) wind power
E) geothermal energy

Question 20

Desalination of seawater by reverse osmosis requires application of a pressure in excess of the solutions osmotic pressure.What is the osmotic pressure of a 5.0 g NaCl/L solution at 25 ^$\circ$ C? (assume the van't Hoff factor i = 2; R = 0.0826 L.atm/mol.K)

A) 4.2 atm
B) 2.1 atm
C) 0.35 atm
D) 250 atm
E) 21 atm

Question 21

Many homes are heated using natural gas.The combustion of natural gas converts

A) chemical potential energy to thermal energy.
B) thermal energy to mechanical energy.
C) mechanical energy to chemical potential.
D) electrostatic energy to mechanical energy.
E) gravitational energy to acoustic energy.

Question 22

What mass of sulfur dioxide gas would be produced from 6.00 kg of coal which contains 1.15 % sulfur by mass?

A) 276 g
B) 12.0 g
C) 34.5 g
D) 138 g
E) 103 g

Question 23

Most hydrogen gas is produced industrially by

A) electrolysis.
B) solar energy.
C) steam reforming.
D) bacteria.
E) fuel cells.

Question 24

What process is used to covert coal into coke?

A) steam reforming
B) liquefaction
C) fermentation
D) heating in the absence of air
E) heating in air

Question 25

What form of radiation is trapped by greenhouse gases?

A) microwaves
B) UV radiation
C) visible radiation
D) infrared radiation
E) radio waves

Question 26

Which of the following cannot be used in the production of bioethanol?

A) cellulose from grasses
B) sugar beets
C) sugar cane
D) corn
E) natural gas

Question 27

Which of the following is $\underline{\text{ not }}$ a component of petroleum?

A) alkynes
B) alkenes
C) alkanes
D) A and B
E) A,B,and C

Question 28

The largest known source of tar sands is found in

A) the United States of America.
B) United Arab Emirates.
C) Venezuela.
D) Saudi Arabia.
E) Canada.

Question 29

What quantity,in moles,of oxygen is consumed when 369.3 kJ of energy is evolved from the combustion of a mixture of H₂(g)and O₂(g)?
H₂(g)+ O₂(g) $\to$ H₂O( $\ell$ ); $\Delta$ _rH° = -285.8 kJ/mol-rxn

A) 0.6461 mol
B) 1.292 mol
C) 0.3869 mol
D) 1.146 mol
E) 0.1461 mol

Question 30

Methanol reacts with oils and fats to produce biodiesel through a ___ reaction.

A) trans-esterfication
B) addition
C) condensation
D) alkylation
E) substitution

Question 31

The majority of crude oil ends up being used

A) to make synthetic fibers.
B) to make fine chemicals.
C) to make plastics.
D) as fuel.
E) to make rubber.

Question 32

Rank the three forms of coal,lignite,bituminous,and anthracite,from lowest to highest sulfur content.

A) anthracite < lignite < bituminous
B) lignite < anthracite < bituminous
C) lignite < bituminous < anthracite
D) anthracite < bituminous < lignite
E) bituminous < lignite < anthracite

Question 33

Which of the following statements concerning natural gas is $\underline{\text{not }}$ true.

A) Gas fired power plants emit up to 40% less CO₂ than coal fired power plants.
B) 70-95% of natural gas consists primarily of ethane (C₂H₆).
C) Combustion of methane does not produce ash.
D) Large amounts of methane exist in the oceans as methane hydrates.
E) Natural gas is refined before it is transported to distributed for use.

Question 34

A byproduct of biodiesel production is

A) methanol
B) glycerol
C) water
D) hydrogen
E) glucose

Question 35

In addition to electricity,what products are generated by a fuel cell charged with methanol (CH₃OH)and dioxygen (O₂)?

A) H₂
B) H₂ and CO
C) H₂ and CH₄
D) H₂O and CH₄
E) H₂O and CO₂

Question 36

What process is used to covert coal into coke?

A) steam reforming
B) liquefaction
C) fermentation
D) heating in the absence of air
E) heating in air

Question 37

Which of the following is not a greenhouse gas?

A) CO₂
B) CH₄
C) H₂O
D) N₂O
E) N₂

Question 38

Biodiesel is a mixture of

A) fats and oils derived from glycerol.
B) alkenes derived from fats and oils.
C) ketones derived from fatty acids.
D) esters derived from fats and oils.
E) fatty acids derived from fats and oils.

Question 39

Calculate the mass of coal that produces the same amount of energy when burned as the combustion of 3.53 kg H₂.

A) kg
B) kg
C) 15 kg
D) 0.85 kg
E) kg

Question 40

At constant pressure and 25 ^$\circ$ C,what is $\Delta$ _rH ^$\circ$ for the following reaction

2C₂H₆(g)+ 7O₂(g) $\to$ 4CO₂(g)+ H₂O( $\ell$ )
If the complete consumption of 16.1 g of C₂H₆ liberates -835.3 kJ of heat energy?

A) -3120 kJ/mol-rxn
B) -1560 kJ/mol-rxn
C) -895 kJ/mol-rxn
D) -447 kJ/mol-rxn
E) -787 kJ/mol-rxn

Question 41

What is wrong with the statement,"To stop global worming we must eliminate all greenhouse gases."?

Question 42

Explain why the melting of Arctic sea ice will not raise the sea level.

Question 43

The surface temperature of the Earth has risen in the last 200 years approximately

A) < 0.5 ^$\circ$ C
B) 1 ^$\circ$ C
C) 5 ^$\circ$ C
D) 10 ^$\circ$ C
E) 15 ^$\circ$ C

Question 44

Ocean acidification is the result of the increasing atmospheric concentration of what gas?

A) CH₄
B) NO₂
C) CO₂
D) SO₂
E) SO₃

Question 45

The pH of the oceans in the 18th century was 8. 2.What would the pH be if the hydronium concentration of the oceans was doubled?

A) 16.4
B) 9.28.0
C) 8.0
D) 7.9
E) 4.1

Question 46

Explain why fossil fuels,hydrocarbons produced by natural processes,are considered a nonrenewable energy resource.

Question 47

Carbonic acid is a diprotic weak acid.Which of the following balanced equilibria represents K_a2 for H₂CO₃?

A) CO₃^2-(aq)+ H₂O( $\ell$ ) $\leftrightarrows$ OH^-(aq)+ HCO₃^-(aq)
B) CO₂(g)+ H₂O( $\ell$ ) $\leftrightarrows$ H₂CO₃(aq)
C) H₂CO₃(aq)+ H₂O( $\ell$ ) $\leftrightarrows$ H₃O⁺(aq)+ HCO₃^-(aq)
D) HCO₃^-(aq)+ H₂O( $\ell$ ) $\leftrightarrows$ OH^-(aq)+ H₂CO₃(aq)
E) HCO₃^-(aq)+ H₂O( $\ell$ ) $\leftrightarrows$ H₃O⁺(aq)+ CO₃^2-(aq)

Question 48

One liter of water is mixed with excess CaCO3(s),setting up the following equilibrium.CaCO₃(s) $\leftrightarrows$ Ca²⁺(aq)+ CO₃^2-(aq)
What is the effect on the solubility of CaCO₃(s)as HNO₃(aq)is added? (assume no change in volume)

A) the solubility of CaCO₃ decreases because the acid increases the amount of CO₃^2-
B) the solubility of CaCO₃ increases because the acid increases the amount of CO₃^2-
C) the solubility of CaCO₃ decreases because the acid decreases the amount of CO₃^2-
D) the solubility of CaCO₃ increases because the acid decreases the amount of CO₃^2-
E) the solubility of CaCO₃ is unchanged