PS100 Unit 3

How many hydrogen atoms are in three cis-platin molecules (3PtCl2N2H6)?

18

If the activity of a radioactive substance drops to 1/16 its initial value in 12 hours, its half life is (A) 2 hours. (B) 3 hours. (C) 6 hours. (D) 16 hours. (E) none of these.

(B) 3 hours.

The mass of a chlorine atom in atomic mass units is approximately 35. The atom has (A) 35 neutrons. (B) 35 protons. (C) 18 neutrons. (D) 35 electrons. (E) 17 neutrons.

(C) 18 neutrons.

Of the following varieties of matter, the strongest bonds are found in A. atomic matter B. molecular matter C. network matter D. pure substances E. mixtures

C. network matter

Which of the following is not a compound? A. sulfur dioxide B. nitrous oxide C. water molecule D. oxygen molecule E. rust

D. oxygen molecule

Which of the following processes is closest to an ideal reversible process? (A) Two cars colliding. (B) Using a toaster to make toast. (C) A pendulum swinging with almost no friction. (D) A ripe peach rotting. (E) An ice cube melting in a glass of warm water.

(C) A pendulum swinging with almost no friction.

Use the Periodic Table to decide if S is a metal or a nonmetal. Do the same for O. If these two form a compound, which of the following characteristics will it show at room temperature? (A) Brittle, transparent, electrically non conducting solid. (B) Electrically conducting, metallic alloy. (C) Transparent gas. (D) The elements listed are very unlikely to react with one another. (E) Electrically nonconducting, metallic alloy.

(C) Transparent gas.

In which kind of radioactive decay would the number of protons in the resulting nucleus be more than in the initial nucleus? (A) alpha decay. (B) gamma decay. (C) beta decay.

(C) beta decay.

Which of the following is atomic matter rather than molecular or network matter? a. Neon gas b. water c. magnesium chloride d. silver e. white gold

a. Neon gas

When you compare saturated with unsaturated fatty acids containing the same number of carbon atoms, what is true? a. Saturated fatty acids have more hydrogen atoms. b. Saturated fatty acids have more oxygen atoms. c. Saturated fatty acids are more curved. d. Saturated fatty acids have lower melting points. e. Saturated fatty acids have more double bonds.

a. Saturated fatty acids have more hydrogen atoms.

Each molecule of nitric acid has the formula HNO3. If there are 6000 oxygen atoms present and 6000 nitrogen atoms present, how many hydrogen atoms will be required to convert all of the oxygen atoms into nitric acid? a. 1000 b. 2000 c. 4000 d. 6000 e. 18000

b. 2000

Uranium-238 alpha decays, emitting a helium-4 nucleus. What is the mass number of the product? a. 230 b. 234 c. 238 d. 242 e. 246

b. 234

In order to have a "full" shell, most atoms 'want' to have

8

Which ion would Ca most likely form? A. Ca2+ B. Ca2- C. Ca6- D. Ca+

A. Ca2+

Sugar is a covalent molecule that is solid at room temperature and disolves easily in water. What does this information tell us about the molecule? A. Sugar molecules are polar B. Sugar molecules are long straight molecules with no kinks C. Sugar molecules are ionic D. Sugar molecules contain double bonds. E. Sugar contains hydrogen and oxygen just like water

A. Sugar molecules are polar

Ionic Bond A. The bond between a metal and a nonmetal B. The bond between two nonmetal atoms C. The bond between two metal atoms

A. The bond between a metal and a nonmetal

Baking soda and vinegar combine to make sodium acetate, carbon dioxide, and water. In this chemical reaction the reactants are the baking soda and vinegar A. True B. False

A. True

Polar molecules dissolve easily in water. A. True B. False

A. True

A proton has a mass that is ______________ than the mass of a neutron. A. Much less B. About the same C. Much greater

B. About the same

Dispersion forces, polar forces and hydrogen bonding are all types of bonds that hold atoms together to make molecules and compounds. A. True B. False

B. False

Which of the following is the most ordered? A. Nuclear potential energy B. Kinetic energy C. Chemical potential energy D. Thermal energy E. Electrical potential energy

B. Kinetic energy

Leaving the door of the refrigerator open on a hot summer day will eventually have the effect of A. cooling down the room B. warming up the room C. leaving the room at the same temperature as it would be with the door closed D. not enough information is provided to decide

B. warming up the room

Suppose the carbon and oxygen react according to the equation: O2 + 2C = 2CO. If you started with sixty oxygen molecules (60O2) and sixty carbon(60C), how many carbon monoxide molecules could you make? A. 6 B. 30 C. 60 D. 120 E. There could be no reaction because you don't have the right number of atoms.

C. 60

What happens to the valence electrons as the product (MgO) is formed? a. The orbitals spread out into the whole solid and overlap. b. The magnesium atoms' valence electrons are effectively transferred to oxygen. c. The oxygen atoms' valence electrons are effectively transferred to magnesium. d. The orbitals of both atoms' valence electrons change shape so that the electrons are shared equally between the atoms. e. The electrons move to new orbitals that are higher in energy than the individual atomic orbitals.

b. The magnesium atoms' valence electrons are effectively transferred to oxygen.

Which of the following is NOT why alloys are useful to us today? Alloys a. have lower melting temperatures. b. have a higher conductivity rate. c. are less malleable. d. reduce weight in objects.

b. have a higher conductivity rate.

Double bonds are found in A. saturated fatty acids B. unsaturated fatty acids C. both A and B D. neither A or B

B. unsaturated fatty acids

How do semiconductors change with increasing temperatures? A. When you heat them up, semiconductors act more like metals. B. When you heat them up, semiconductors become better insulators. C. When you heat them up, semiconductors become more transparent

A. When you heat them up, semiconductors act more like metals.

Metals have higher ionization energies than non-metals do. A. True B. False

B. False

When we increase the temperature of the material A. the conductivity of metals and semi-conductors increase B. the conductivity of metals and semi-conductors decrease C. the conductivity of metals increases whereas that of semi-conductors decreases D. the conductivity of metals decreases whereas that of semi-conductors increases E. the conductivity of semi-conductors does not change

D. the conductivity of metals decreases whereas that of semi-conductors increases

Which of the following statements is true? A. It is not possible to convert the kinetic energy of a car into elastic energy B. It is not possible to convert nuclear potential energy into kinetic energy of rocks C. It is not possible to convert thermal energy into any other kind of energy D. all of the above E. none of the above

E. none of the above

Locate the elements palladium (Pd, atomic #46) and nickel (Ni, atomic #28) on the periodic table. If Pd is combined with Ni, which of the following characteristics will the product show at room temperature? a. Non-conducting, transparent solid. b. Shiny, malleable solid. c. Transparent gas. d. Brittle, opaque solid. e. Opaque gas.

b. Shiny, malleable solid.

Covalent Bond A. The bond between a metal and a nonmetal B. The bond between two nonmetal atoms C. The bond between two metal atoms

B. The bond between two nonmetal atoms

Salts have which of the following properties? A. Conduct electricity B. Transparent C. Ionic bonds D. Combination of metal and nonmetal atoms E. Malleable

B. Transparent C. Ionic bonds D. Combination of metal and nonmetal atoms

Glucose is ... A. polar and therefore sticky B. non-polar and therefore sticky C. polar and therefore non-sticky D. non-polar and therefore non-sticky E. none of the above

A. polar and therefore sticky

Why is a high temperature required for nuclear fusion to occur? a. High temperatures are required to allow the nuclei to have enough kinetic energy to overcome the electromagnetic repulsion and have the strong force attraction take place. b. High temperatures magnify the strong force attraction and allow fusion to occur more readily. c. High temperatures are required to keep the fusion fuel, deuterium and tritium, stable. d. High temperatures cause the electromagnetic force to change from a repulsive force to an attractive force which helps the strong force combine the two nuclei.

a. High temperatures are required to allow the nuclei to have enough kinetic energy to overcome the electromagnetic repulsion and have the strong force attraction take place.

When you compare the band gap for a red and a blue LED, what is true? a. The red LED has the smallest band gap. b. The blue LED has the smallest band gap. c. The band gaps are equal as long as the battery powering them is the same. d. The color of light doesn't have anything to do with the band gap.

a. The red LED has the smallest band gap.

Which of the following would best describe the characteristics of covalent materials? a. A brittle, transparent solid with a very high melting point. b. A shiny, malleable solid with a very high melting point. c. A non-conducting material with low melting and boiling points, likely liquid or gas at room temperature. d. A brittle, opaque solid with a very high melting point. e. A non-conducting solid at room temperature that will conduct if melted or dissolved.

c. A non-conducting material with low melting and boiling points, likely liquid or gas at room temperature.

Metals have which of the following properties? A. Metals are good electrical conductors. B. Metals are poor conductors of heat. C. Metals are shiny. D. Metals are malleable. E. Metals are not very reactive with other elements. F. Metals easily form alloys. G. Metals form hard crystals with sharp faces. H. Metals are transparent.

A. Metals are good electrical conductors. C. Metals are shiny. D. Metals are malleable. F. Metals easily form alloys.

A refrigerator is normally run with its door closed. What would happen if the refrigerator were placed in the middle of a closed room with its door open and turned on? A. The room would heat up because all of the energy absorbed by the refrigerator, both thermal and electrical potential, is released back into the room as thermal energy. B. The room would heat up because the electrical potential energy loses entropy while the room gains entropy. C. The temperature of the room would stay the same because internal energy is conserved. D. The room would cool down because as the entropy of the electrical potential energy increases, the entropy of the room must decrease to compensate. E. The room would cool down because the electrical potential energy from the outlet decreases the ambient thermal energy in the room.

A. The room would heat up because all of the energy absorbed by the refrigerator, both thermal and electrical potential, is released back into the room as thermal energy.

In fission, nuclei A. split such that the average mass per nucleon goes down B. split such that the average mass per nucleon goes up C. fuse such that the average mass per nucleon goes down D. fuse such that the average mass per nucleon goes up E. none of the above

A. split such that the average mass per nucleon goes down

If a molecular material is solid at room temperature, the high melting and boiling temperatures indicate there must be polar forces holding the molecules together. A. True B. False

B. False

Match the characteristics of nuclear processes with the correct process. Fuel for the process is relatively plentiful on earth A. Fission B. Fusion

B. Fusion

Match the characteristics of nuclear processes with the correct process. It combines small nuclei to make larger ones A. Fission B. Fusion

B. Fusion

Match the characteristics of nuclear processes with the correct process. Primary process in the most powerful nuclear weapons A. Fission B. Fusion

B. Fusion

In order to fill their orbitals and satisfy the octet rule, non-metals will typically A. attract extra electrons, just like metals do B. attract extra electrons, unlike metals C. get rid of electrons, like metals do D. get rid of electrons, unlike metals E. none of the above

B. attract extra electrons, unlike metals

When sodium (Na) and Chlorine (Cl) form table salt (NaCl) the chlorine atoms A. turn into chlorine molecules B. become positively charged chlorine ions C. become negatively charged chlorine ions D. move up (right) one spot in the periodic table, towards sodium E. move down (left) one spot in the periodic table, towards the noble gases

C. become negatively charged chlorine ions

Which of the following set of properties is most likely those associated with methane, a covalently bonded compound? A. solid at room temperature, opaque, good electrical conductor B. solid at room temperature, transparent, electrical conductor when dissolved in water C. gas at room temperature, colorless, does not conduct electricity when solid

C. gas at room temperature, colorless, does not conduct electricity when solid

Which of the following would best describe the room temperature characteristics of the magnesium oxide? a. Brittle, opaque, solid. b. Electrically conducting alloy. c. Transparent gas. d. A malleable solid. e. Brittle, transparent, electrically non-conducting solid.

e. Brittle, transparent, electrically non-conducting solid.

What is the charge of iron (Fe) in the compound Fe2O3? A. -3 B. -2 C. +2 D. +3

D. +3

Which of the following is NOT a characteristic of a metal or alloy? A. Electrically Conductive B. Thermally Conductive C. Malleable D. Brittle

D. Brittle

Which of the following would best describe the room temperature characteristics of ionic substances? A. Electrically conducting alloy. B. Transparent gas. C. A malleable solid. D. Brittle, non-conducting solid with high melting points.

D. Brittle, non-conducting solid with high melting points.

For the Butylene molecule C above, what forces would be the largest forces holding one of the molecules to another molecule? (What are the largest intermolecular forces?) A. Covalent bonds B. Dipole bonds C. Hydrogen bonds D. Dispersion forces

D. Dispersion forces

A window air conditioner is normally placed in a window so the hot air from the back blows outside. What would happen if the air conditioner were placed in the middle of a closed room and turned on? Select one: a. The room would heat up because all of the energy absorbed by the air conditioner, both thermal and electrical potential, is released back into the room as thermal energy. b. The room would heat up because the electrical potential energy loses entropy while the room gains entropy. c. The temperature of the room would stay the same because internal energy is conserved. d. The room would cool down because as the entropy of the electrical potential energy increases, the entropy of the room must decrease to compensate. e. The room would cool down because the electrical potential energy from the outlet decreases the ambient thermal energy in the room.

a. The room would heat up because all of the energy absorbed by the air conditioner, both thermal and electrical potential, is released back into the room as thermal energy.

The purpose of the control rods in a nuclear fission reactor is a. to slow down the neutrons, since slower neutrons have a higher probability of causing fission. b. to absorb neutrons, thus limiting the number of nuclei undergoing fission. c. to increase the number of neutrons by causing nuclear reactions in the control rods, so that more nuclei in the fuel will undergo fission. d. to act as spacers to keep the fuel elements apart. e. to contain material to be transformed into new fissionable fuel by neutron irradiation.

b. to absorb neutrons, thus limiting the number of nuclei undergoing fission.

Which of the equations below is balanced correctly? a. Mg + N2 = MgN3 b. 2P2 + O2 = P2O5 c. CH4 +2O2 = CO2 + 2H2O d. 2Zn + O2 = ZnO e. 2C + O2 = 2CO2

c. CH4 +2O2 = CO2 + 2H2O

Both fission and fusion can result in a release of energy. Why? a. The strong force is attractive over short distances and repulsive at larger distances. b. Any change to a nucleus is going to convert mass into energy. c. The nuclei of atoms with a mass of about 50 have the smallest average nucleon mass and the least energy. d. Either combining large nuclei or splitting small nuclei results in an increase in energy. This energy is released as heat.

c. The nuclei of atoms with a mass of about 50 have the smallest average nucleon mass and the least energy.

In an irreversible process, the overall disorder of the universe a. is constant. b. decreases. c. increases. d. is zero. e. becomes infinite.

c. increases.

The 2nd Law of Thermodynamics (Law of Increasing Disorder) places limits on the efficiency of energy conversion. Which of the following is allowed? a. 100% conversion of ambient temperature thermal energy to kinetic energy. b. 100% conversion of chemical potential energy to kinetic energy. c. 100% conversion of sunlight to kinetic energy. d. 100% conversion of electricity to ambient temperature thermal energy. e. 100% conversion of ambient temperature thermal energy to chemical potential energy.

d. 100% conversion of electricity to ambient temperature thermal energy.

What happens to the entropy of the universe as the products are formed? a. The total entropy stays the same. b. Thermal energy is converted into electromagnetic energy resulting in a decrease in total entropy. c. Chemical bonds are formed resulting in a decrease in total entropy. d. Chemical potential energy is converted into kinetic energy resulting in a decrease in entropy. e. Chemical potential energy is converted into thermal energy resulting in an increase in entropy.

e. Chemical potential energy is converted into thermal energy resulting in an increase in entropy.

Why are metals opaque? a. because the atoms are closer together than the wavelength of light b. because metals are good conductors c. because metals are malleable d. because metals have high melting and boiling points e. because metals have empty, overlapping orbitals for their electrons

e. because metals have empty, overlapping orbitals for their electrons

How would you determine the following from information found on the periodic table? Number of Protons A. Atomic number B. Mass number C. Atomic number but only in a neutral atom D. Sum of atomic number plus mass number E. Difference of mass number minus atomic number

A. Atomic number

Match the characteristics of nuclear processes with the correct process. It has been harnessed for commercial electricity generation A. Fission B. Fusion

A. Fission

Match the characteristics of nuclear processes with the correct process. It involves breaking up large nuclei into smaller ones A. Fission B. Fusion

A. Fission

Match the characteristics of nuclear processes with the correct process. It occurs on the sun A. Fission B. Fusion

A. Fission

How would you determine the following from information found on the periodic table? Number of Electrons A. Atomic number B. Mass number C. Atomic number but only in a neutral atom D. Sum of atomic number plus mass number E. Difference of mass number minus atomic number

C. Atomic number but only in a neutral atom

Metallic Bond A. The bond between a metal and a nonmetal B. The bond between two nonmetal atoms C. The bond between two metal atoms

C. The bond between two metal atoms

What does half-life mean? A. The time it takes for a nucleus to lose half of its mass. B. Half the time it would take for all of the nuclei to decay. C. The time it takes for half of all the nuclei to decay. D. Half of the time it takes for a single nucleus to completely decay.

C. The time it takes for half of all the nuclei to decay.

The possible link between trans-fatty acids and the occurrence of health problems may be due to the fact that they... A. have more double bonds than cis fatty acids B. have fewer double bonds than cis fatty acids C. are straighter than cis fatty acids D. are less straight than cis fatty acids E. none of the above

C. are straighter than cis fatty acids

Reactions are most likely to occur when the chemical system A. increases its energy and entropy B. decreases its energy and entropy C. increases its energy but decreases its entropy D. decreases its energy but increases its entropy E. none of the above, since energy is always conserved

D. decreases its energy but increases its entropy

A metal can best be described as which of the following? A. A network solid consisting of individual negatively charged atoms B. A network solid consisting of positively-charged and negatively-charged ions C. A molecular solid consisting of charged atoms D. An ionic solid consisting of covalently-bonded atoms E. A network solid consisting of positively charged atoms in a sea of electrons

E. A network solid consisting of positively charged atoms in a sea of electrons

What happens to the entropy of the universe as the products are formed in an exothermic chemical reaction? A. The total entropy stays the same. B. Thermal energy is converted into electromagnetic energy resulting in a decrease in total entropy. C. Chemical bonds are formed resulting in a decrease in total entropy. D. Chemical potential energy is converted into kinetic energy resulting in a decrease in entropy. E. Chemical potential energy is converted into thermal energy resulting in an increase in entropy.

E. Chemical potential energy is converted into thermal energy resulting in an increase in entropy.

How would you determine the following from information found on the periodic table? Number of Neutrons A. Atomic number B. Mass number C. Atomic number but only in a neutral atom D. Sum of atomic number plus mass number E. Difference of mass number minus atomic number

E. Difference of mass number minus atomic number

Partially filled bands lead to materials that tend to A. be opaque B. be malleable C. conduct heat well D. conduct electricity well E. all of the above

E. all of the above

In the equation C2H4 + 3O2 = ? CO2 + 2H2O, how many CO2 molecules are needed to balance the equation? a. 2 b. 3 c. 4 d. 5

a. 2

In which of the following processes is the end product more ordered than the reactants? (In which process does entropy decrease.) a. 2H2 (gas) + O2 (gas) = 2 H2O (gas) b. 2C8H18 (liquid) + 25O2 (gas) = 16CO2 (gas) + 18H2O(gas) c. C6H12O6 (solid) + 6O2 (gas) = 6CO2 (gas) + 6H2O (liquid) d. 2C7H5N3O6 (solid) = 3N2(gas) + 7CO(gas) + 5H2O(gas) + 7 C(solid) e. NaHCO3(solid) + C2H4O2(liquid)=C2H3NaO2(solid)+ H2O(liquid) + CO2(gas)

a. 2H2 (gas) + O2 (gas) = 2 H2O (gas)

In order for a chemical reaction to occur: Select one: a. Energy must decrease as a result of the reaction. b. Entropy must increase as a result of the reaction. c. Energy and entropy must both increase. d. Energy and entropy must both decrease. e. Energy must decrease and entropy must increase.

b. Entropy must increase as a result of the reaction.

Which type of energy listed below is the most ordered? a. Nuclear potential energy b. Gravitational potential energy c. Thermal energy d. Chemical potential energy d. Impossible to tell without more information about the process.

b. Gravitational potential energy

Which of the following is a correct comparison of metals and semi-conductors? a. Metals have a larger band gap than semi-conductors. b. Metals' resistance increases when temperature increases while a semi-conductors resistance decreases. c. Semi-conductors' molecular orbitals overlap while metals' don't. d. Metals have more valence electrons than semi-conductors. e. Metals have larger electrical resistance than semi-conductors.

b. Metals' resistance increases when temperature increases while a semi-conductors resistance decreases.

When you compare the mass of the products to the mass of the reactants in a fission reaction, what do you find? (note the question is asking about mass, not mass number) a. The products have more mass b. The reactants have more mass c. The mass is the same on each side

b. The reactants have more mass

Which of the following is a correct and balanced equation showing the reaction of calcium and oxygen? (While several of the equations may be balanced, only one has the correct products and reactants as well as being correctly balanced.) a. Ca + O2 = CaO b. Ca + O2 = CaO2 c. 2Ca + O2 = 2CaO d. 4Ca + O2 = 2Ca2O e. Ca + O2 = Ca2O

c. 2Ca + O2 = 2CaO

What is the charge of iron (Fe) in the compound Fe2O3? a. -3 b. -2 c. +2 d. +3

d. +3

Which of the following is a true statement about melting and boiling points in materials made of covalent molecules? a. Molecules that contain double bonds melt and boil at higher temperatures because the bonds are stronger. b. Molecules that contain triple bonds are the most likely to be gases at room temperature. c. Molecules that are polar have lower melting and boiling points than non-polar molecules. d. Hydrogen bonding between molecules increases melting and boiling points. e. Van der Waals (dispersion) forces lower melting and boiling points.

d. Hydrogen bonding between molecules increases melting and boiling points.

What best describes how oxygen molecules would behave if mixed with water? a. They would dissolve well because they are polar. b. They would dissolve well because they are not polar. c. They would dissolve poorly or not at all because they are polar. d. They would dissolve poorly or not at all because they are not polar. e. They would dissolve well because they are ionic.

d. They would dissolve poorly or not at all because they are not polar.

Which of the following processes is closest to an ideal reversible process? a. Two cars colliding. b. Using a toaster to make toast. c. A pendulum swinging. d. A ripe peach rotting. e. An ice cube floating in a glass of water at zero degrees.

e. An ice cube floating in a glass of water at zero degrees.

Which of the following elements form diatomic gases? A. Sodium (Na) B. Oxygen (O) C. Helium (He) D. Zirconium (Zr) E. Nitrogen (N) F. Hydrogen (H) G. Chlorine (Cl) H. Neon (Ne)

hydrogen, nitrogen, oxygen, chlorine

Two atoms that have the same atomic numbers but different atomic mass numbers are called

isotopes

Which of the following correctly describes the ranges of forces between charged nucleons in nuclear physics? "Short distances" refers to distances about the size of the diameter of a nucleon. (A) The strong interaction is about as strong as the electromagnetic interaction at short distances, but becomes much weaker at long distances. (B) The electromagnetic interaction is stronger than the strong interaction at short distances, but weaker at sufficiently long distances. (C) The strong interaction is stronger than the electromagnetic interaction at all distances. (D) The strong interaction is stronger than the electromagnetic interaction at short distances, but the reverse is true at sufficiently long distances. (E) The strong interaction is about as strong as the electromagnetic interaction at short distances, but becomes much stronger at long distances.

(D) The strong interaction is stronger than the electromagnetic interaction at short distances, but the reverse is true at sufficiently long distances.

The primary obstacle to controlled fusion reactions as a source of energy is (A) the scarcity of fuel (deuterium). (B) the danger of long lived radioactive wastes. (C) the danger of a runaway reaction. (D) overcoming the electromagnetic repulsion of particles with like charges. (E) the scarcity of suitable material for control rods.

(D) overcoming the electromagnetic repulsion of particles with like charges.

How does a catalyst affect a reaction? a. It raises the activation entropy b. It changes anti-bonding orbitals into bonding orbitals c. It lowers the band gap d. It lowers the activation energy e. It increases the energy of the transition state

d. It lowers the activation energy

Listed below are the common names and contents for a number of common substances. Four are compounds, one is not. Which is not a compound? (A) sulfur dioxide, consisting of molecules having one S and two O atoms. (B) hydrochloric acid, consisting of molecules having one H and one Cl atom. (C) sulfur, consisting of molecules having eight S atoms. (D) carbon monoxide, consisting of molecules having one C and one O atom. (E) nitric oxide, consisting of molecules having one N and one O atom.

(C) sulfur, consisting of molecules having eight S atoms.

The modern definition of an element is a substance made up of atoms that all have the same number of A. Nucleons B. Neutrons C. Muons D. Protons

D. Protons

The gasoline engine of an automobile is considerably less than 100% efficient. This means that not all of the energy in the gasoline is turned into kinetic energy of the car. Which of the following best explains why? A. Engineers and scientists have not yet managed to make it more efficient, but there is no scientific reason it cannot be 100% efficient. B. There is too much friction in the engine and the rest of the automobile. If it were not for this friction the efficiency would be 100%. C. All engines (that is electric motors, gasoline engines, steam power generators burning gas or oil, etc) have exactly the same efficiency, which is, of course, less than 100%. D. Some of the chemical potential energy in the gasoline must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted. E. Actually the automobile engine is nearly 100% efficient as long as the automobile is traveling on the level. When it climbs up a hill, however, the efficiency drops because of the changing gravitational potential energy

D. Some of the chemical potential energy in the gasoline must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted.

Which of the following is the least ordered? A. Nuclear potential energy B. Kinetic energy C. Chemical potential energy D. Thermal energy E.Electrical potential energy

D. Thermal energy

In order to get a more vigorous reaction you should A. increase the concentration of atoms B. increase the pressure C. increase the temperature D. all of the above E. more than one, but not all of the above

D. all of the above

How does the mass of a proton compare to the mass of an electron? A. Much less than the electron B. A little less than the electron C. About the same as the electron D. A little bit larger than the electron E. Much larger than the electron

E. Much larger than the electron

What do aspirin, naproxen, and ibuprofen have in common (as seen in Fig. 19.5) A. single bonds B. double bonds C. benzene-like rings D. oxygen atoms E. all of the above

E. all of the above

Which of the following fatty acids is best for human health? a. Fatty acids that only have single bonds between carbon atoms. b. Fatty acids that have one or more 'straight' trans-double bonds between carbon atoms. c. Fatty acids that have one or more 'bent' cis-double bonds between carbon atoms. d. All are equally bad for your health.

c. Fatty acids that have one or more 'bent' cis-double bonds between carbon atoms.

Which of the following tends to have the highest melting and boiling points? a. Atomic matter b. molecular matter c. network matter

c. network matter

The gasoline engine of an automobile is considerably less than 100% efficient. This means that not all of the energy in the gasoline is turned into kinetic energy of the car. Which of the following best explains why? a. Engineers and scientists have not yet managed to make it more efficient, but there is no scientific reason it cannot be 100% efficient. b. There is too much friction in the engine and the rest of the automobile. If it were not for this friction the efficiency would be 100%. c. All engines (that is electric motors, gasoline engines, steam power generators burning gas or oil, etc) have exactly the same efficiency, which is, of course, less than 100%. d. Some of the chemical potential energy in the gasoline must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted. e. Actually the automobile engine is nearly 100% efficient as long as the automobile is traveling on the level. When it climbs up a hill, however, the efficiency drops because of the changing gravitational potential energy

d. Some of the chemical potential energy in the gasoline must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted.