CHM 1020 - Final Exam Review

2.36 x 10^6 J

A Big Mac has a nutritional value of 563 Calories (Cal). Express this value in joules. (1 Cal = 1000 cal, 1 cal = 4.184 J)

Molecule

A _______ is a fixed number of atoms held together by chemical bonds in a certain spatial arrangement

exothermic

A chemical reaction accompanied by a release of energy is called an ________ reaction.

2.1 x 10^12 g

A coal burning power plant generates 6.0 x 10^16 J per year. If the combustion of coal yields 29 kJ/g, how many grams of coal was burned each year?

6.1 x 10^16 J

A coal-burning power plant generates electrical power at a rate of 750 megawatts (MW), or 7.50 x 10^8 J/s. The plant has an overall efficiency of 39% for the conversion of heat to electricity. Given this efficiency, how much heat energy in Joules (J) is produced in one year of operation?

25000 ppm (percents is parts per hundred)

A particular sample of air is 2.5 percent water vapor. Express the concentration of water vapor in parts per million (ppm)

compound

A substance that can be broken down into two or more simpler substances by chemical methods is called a

second law of thermodynamics

Advertising claims that sometimes state that adding something mechanical to a car's engine will allow it to recover 100 percent of the energy that comes from burning gasoline. You should be skeptical of such claims because they violate the

CO

All of these pollutants can be detected by their orders except

Reintroducing the use of tetraethyl lead to increase the octane rating of gasoline

Alternative energy sources are currently being researched in effort to replace our dependence on fossil fuels. Which is not a current research effort in this regard?

is an endothermic process

Any chemical of physical change that absorbs energy

0.126 tons

Assume that coal can be represented by the chemical formula C135H96O9NS. If 15.0 tons of coal is burned, what MASS OF SULFUR is formed in the SO2 produced by this process?

remove suspended clay and dust particles

At water treatment plants aluminum sulfate and calcium hydroxide are added to

Methane

Based on its name, which carbon compound contains the fewest carbon atoms?

1.16 x 10^-18 g

Calculate the mass of 25,000 molecules of nitrogen gas. (1 mole = 6.02 x 10^23 molecules)

interact with UV energy to produce free radicals that destroy ozone

Chlorofluorocarbons rise to the stratosphere and

1,3,2,2

Choose the proper coefficients for each substance to balance this equation. ___ C2H4(g) + ___ O2(g) → ___ CO2(g) + ___ H2O(g)

coal burning power plants

Currently, the primary source of sulfur dioxide emissions into the atmosphere is

ultraviolet region, especially below a wavelength of 320 nm

DNA, the genetic material of living organisms, is damaged by light in the

The heat of the sun drives large-scale movements of air

How is wind energy related to the sun?

2.26 x 10^23

How many atoms are present in 0.375 mol of palladium (Pd) atoms?

3

How many bromide ions can combine with one ion of aluminum to form an ionic compound?

8

How many carbon atoms does the molecule octane have?

1,81 x 10^24 O atoms

How many oxygen atoms are in 6.02 x 10^23 molecules of ozone?

3.0 x 10^26

Hydrogen gas (H2) is a promising alternative to fossil fuels. How many molecules are present in 1.0 kg of hydrogen gas?

Develop alternate energy sources that do not rely on fossil fuels

Identify the single most effective strategy to reduce carbon dioxide emissions.

0.154 M

If you arrive at the hospital with a severe dehydration or decreased blood volume, you may receive an intravenous saline solution known as normal saline (NS). NS typically contains 0.900 grams of NaCl per 100.0 mL of water. What is the molar concentration of NaCl in this solution?

5.08 g

In a 45 minute road trip a vehicle emitted 16.7 g of nitrogen dioxide (NO2) from its exhaust. What is the mass of nitrogen atoms in this amount of NO2?

Light shining on the system must have enough energy to set electrons in motion from the n-type semiconductors to the p-type

In a solar cell, semiconductors of the p-type and n-type are placed in contact with each other via a conducting wire. In order to generate an electric current, which of the following must be true?

heat is released as the reaction proceeds

In an exothermic chemical reaction

carbon monoxide

In general, which airborne material is not likely to be affected by the filters or indoor air handling equipment?

number of waves passing a fixed point in one second

In reference to waves, frequency is the

E = energy, m = mass, and c = speed of light

In the famous equation E=mc2, the symbols represent

those in the same columns

In the periodic table, which elements typically have similar properties?

it separates crude oil into fractions consisting of compounds with similar boiling points

In the petroleum industry, what does a refinery do?

is the ratio of electromagnetic radiation reflected by a surface to the amount of radiation hitting that surface

Land use changes have a big impact on global warming because of their effect on albedo. Albedo

groups

On a periodic table, the columns of elements with similar properties are

electrons

Oxidation and reduction of atoms involves a change in the number of _______ in the atom

troposphere; stratosphere

Ozone is considered an air pollutant in the ________ but is a valuable protective layer in the __________.

hydrocarbons

Petroleum (crude oil) is a complex mixture of thousands of substances, the majority of which are

coal-burning plants

Smokestacks at these plants release sulfur oxides and carbon dioxide into the air.

H20

The _______ concentration in the air over the desert differs dramatically from that in the air in the tropical rainforest

platinum and palladium

The burning characteristics of a gasoline can be improved by converting the octane it contains into isooctane. This conversion requires the use of expensive catalysts such as

activation energy

The energy needed to initiate a chemical reaction is called the

heat

The energy that flows from a warmer body to a colder body is called

biomass

The general term for plant matter such as trees, grasses, agricultural crops, or other biological material is

atmospheric gasses trap and return infrared radiation radiated by Earth

The greenhouse effect refers to the process by which

8.36 x 10^6 kJ

The heat of combustion for n-heptane is 4,187 kJ/mol. How much heat is produced if 200 kg of n-heptane (C7H16) is completely combusted?

51.9 kJ/g

The heat of combustion of ethane, C2H6, is 1560 kJ/mol. What is the heat of combustion of ethane, in kJ per gram?

1,000 times greater

The hydronium ion concentration in a solution with pH 10 is _________ than the hydronium ion concentration in a solution with a pH of 13.

52Cr

The isotope 48Ti is produced by the alpha decay of which of the following?

Troposphere

The lowest (or closest to the ground) layer of our atmosphere is the

to kill disease-causing organisms in the water

The main reason that water supplies are chlorinated is

metals

The most numerous of the elements are the

144Cs

The nuclear fission of 235U can occur via a number of different pathways. If 2 neutrons and 90Rb are produced, what is the other fission product?

144Ce

The nuclear fission of 235U can occur via a number of different pathways. If 3 neutrons and 89Se are produced, what is the other fission product?

4.0 x 10^-3 M

The pH of lemon juice is approximately 2.40. At this pH, the hydronium ion concentration is closest to which concentration?

endothermic; absorbed

The process of cooking an egg is ________ because heat is ____________

1.6 g

Thorium-234 has a t1/2 of roughly 24 days. If 25 g of 234Th was initially present, what mass would remain following 96 days?

False

True or false: the more toxic the pollutant, the higher the concentration is set when concerning air quality standards

3.21 m

WUKF FM transits at 93.5 MHz. What is the wavelength of the electromagnetic radiation that carries the station's signal?

84%

What is the MASS PERCENT of carbon in octane (C8H18)?

23%

What is the MASS PERCENT of fluorine in Halon 1211 (CBrClF2)?

30.9

What is the answer to the following mathematical operation? (1.42 + 9.4) x 2.854

2.47 g/cm^3 (multiply all numbers and divide the weight by the density)

What is the density of a block of material that is 12cm x 6cm x 2cm and has a mass of 356 g?

N2

What is the primary component of an exhaled breath?

12.5 percent

What percentage of a radioactive isotope would remain after three half-lives?

about as large as North America

When it reaches its largest size, the ozone hole over the Antarctic is

polar; form hydrogen bonds with polar water molecules

When the ______ molecules of ethanol, C2H5OH, are added to water, the ethanol molecules __________

Violet

Which color of visible light has the heist frequency?

Chlorofluorocarbons (CFCs)

Which contributes to the ozone hole?

an abundance of sunlight

Which factor did not play a major role in the formation of fossil fuels from plant matter?

inexpensive to operate

Which is not a benefit associated with nuclear power plants?

it is far more abundant than any other fossil fuel

Which is not a known advantage of natural gas over other fossil fuels?

ii and iii only

Which occurrences or processes are expected to reduce the level of atmospheric carbon? i) decaying plant and animal remains. ii) the growth of trees. iii) formation of carbonate rock in the ocean. iv) animal respiration

HFCs

Which of the following compounds is useful for putting out fires and does not deplete stratospheric ozone concentrations?

CH3Cl

Which of these is a trihalomethane?

A nuclear explosion

Which of these is not a realistic risk associated with nuclear power plants?

chlorine atoms

Which product of the ultraviolet decomposition of CFCs acts as the catalyst for ozone decomposition?

ii, iv, and v only

Which substances are regulated by the Kyoto Protocol? i) argon. ii) carbon dioxide. iii) nitrogen. iv) nitrous oxide. v) sulfur hexafluoride