CHAPTER 2 A&P
If an isotope of oxygen has 8 protons, 10 neutrons, and 8 electrons, its mass number is A) 18. B) 12. C) 26. D) 8. E) 16.
A) 18.
Using chemical notation, write the molecular formula for glucose, a compound composed of 6 carbon (C) atoms, 12 hydrogen (H) atoms, and 6 oxygen (O) atoms. (Module 2.7D) A) C6H12O6 B) CH2O C) C1H2O1 D) CHO (6-12-6) E) CHO
A) C6H12O6
________ accelerate chemical reactions that occur in the human body. A) Enzymes B) Products C) Nutrients D) Reactants E) Metabolites
A) Enzymes
Why do our cells need enzymes? (Module 2.9B) A) Enzymes lower the activation energy of a reaction so it can occur. B) Enzymes increase the activation energy of a reaction so it can occur. C) Enzymes are important inorganic compounds used by cells. D) Enzymes are important sources of nutrients. E) Enzymes provide the activation energy of a reaction so it can occur.
A) Enzymes lower the activation energy of a reaction so it can occur.
Which of the following is both an anion and a compound? A) HCO3- B) Cl- C) NaCl D) K+ E) Na+
A) HCO3-
Which of the following statements about water is not correct? A) It has a relatively low heat capacity. B) It is responsible for much of the mass of the human body. C) It can dissolve many substances. D) It contains hydrogen bonds. E) It is composed of polar molecules.
A) It has a relatively low heat capacity.
Describe trace elements. (Module 2.2D) A) Trace elements are present in small amounts in the body and are required for normal growth and maintenance. B) Trace elements are present in small amounts in the body and are not necessary for normal growth and maintenance. C) Trace elements are present in small amounts in the atmosphere but accumulate in the body at high levels. D) Trace elements are the elements produced by nuclear reactions in research laboratories. E) Trace elements are abundant in the atmosphere and also abundant in the human body.
A) Trace elements are present in small amounts in the body and are required for normal growth and maintenance.
Describe the kind of bonds that hold the atoms in a water molecule together. (Module 2.4C) A) Water molecule bonds are polar covalent bonds, in which unequal sharing of electrons occurs. B) Water molecules bonds are nonpolar ionic bonds, in which equal movement of electrons occurs. C) Water molecule bonds are nonpolar covalent bonds, in which equal sharing of electrons occurs. D) Water molecule bonds are oxygen bonds, in which oxygen atoms form bonds together. E) Water molecule bonds are ionic bonds, in which electrons are gained and lost to create the bond.
A) Water molecule bonds are polar covalent bonds, in which unequal sharing of electrons occurs.
When electrons are transferred from one atom to another, and the two atoms unite as a result of the opposite charges, A) an ionic bond is formed. B) a hydrogen bond is formed. C) a free electron is formed. D) an ion is formed. E) a covalent bond is formed.
A) an ionic bond is formed.
In an aqueous solution, cations are attracted toward: A) anions. B) buffers. C) salt. D) hydrogen ions. E) water.
A) anions.
By weight, which element is the second most abundant in the human body? A) carbon B) calcium C) hydrogen D) nitrogen E) oxygen
A) carbon
Ions with a + charge are called: A) cations. B) isotopes. C) positrons. D) radicals. E) anions.
A) cations.
In a molecule of oxygen gas, two pairs of electrons are shared equally by two oxygen atoms. The type of bond that is formed is an example of a A) double polar covalent bond. B) single trivalent bond. C) double nonpolar covalent bond. D) triple nonpolar covalent bond. E) hydrogen bond.
A) double polar covalent bond.
During ionization, water molecules disrupt the ionic bonds of a salt to produce a mixture of ions. These ions can carry a current and so are called A) electrolytes. B) acids. C) anions. D) counter ions. E) cations.
A) electrolytes.
What is an important by-product of exergonic reactions? (Module 2.9C) A) heat B) oxygen C) carbon dioxide D) water E) polymers
A) heat
Which is larger: an element's atomic number or mass number? (Module 2.2A) A) mass number B) atomic number
A) mass number
A solution containing equal numbers of hydrogen ions and hydroxide ions is A) neutral. B) alkaline. C) basic. D) acidic. E) in equilibrium.
A) neutral.
Isotopes of an element differ in the number of: A) neutrons in the nucleus. B) protons in the nucleus. C) electron clouds. D) electrons in the nucleus. E) electrons in energy shells.
A) neutrons in the nucleus.
The molecule O2 is known as: A) oxygen. B) oxygen and organic. C) oxyous. D) oxide. E) organic.
A) oxygen.
Define pH. (Module 2.12A) A) pH is a measure of the hydrogen ion concentration in a solution. B) pH is a measure of blood pressure. C) pH is a measure of the temperature in a solution. D) pH is a measure of the pressure of all the dissolved gases in a solution. E) pH is a measure of the oxygen concentration in a solution.
A) pH is a measure of the hydrogen ion concentration in a solution.
The mass of an atom is largely determined by the number of ________ it has. A) protons + neutrons B) protons C) electrons D) neutrons E) protons + electrons
A) protons + neutrons
The nucleus of an atom consists of A) protons + neutrons B) protons + electrons C) protons D) neutrons E) electrons
A) protons + neutrons
The atomic weight of an atom reflects the average number of: A) protons + neutrons + electrons. B) protons. C) protons + neutrons. D) electrons. E) neutrons.
A) protons + neutrons + electrons.
Which subatomic particles have a positive charge? Which are uncharged? (Module 2.1B) A) protons; neutrons B) protons; electrons C) neutrons; electrons D) electrons; neutrons E) electrons; protons
A) protons; neutrons
Name the participants in a chemical reaction. (Module 2.7A) A) reactants B) cofactors C) enzymes D) vitamins E) products
A) reactants
Hydrophilic molecules readily associate with A) water molecules. B) lipid molecules and hydrophobic molecules. C) cholesterol. D) hydrophobic molecules. E) lipid molecules.
A) water molecules.
In hydrolysis reactions, compounds react with A) water, causing decomposition. B) carbon, causing decomposition. C) glucose, causing decomposition. D) hydrogen, causing decomposition. E) water, causing synthesis.
A) water, causing decomposition.
Calculate the weight of 1 mol of glucose. (The atomic weight of carbon = 12). (Module 2.7E) A) 12 grams B) 180 grams C) 29 grams D) 120 grams E) 24 grams
B) 180 grams
How many electrons are shared by the oxygen atoms in an oxygen molecule? (Module 2.4B) A) 1 pair of electrons B) 2 pairs of electrons C) 3 pairs of electrons D) one electron E) eight electrons
B) 2 pairs of electrons
Define electrolytes. (Module 2.11B) A) Electrolytes are enzymes that lower the activation energy for a solution. B) Electrolytes are ions that will conduct an electrical current in a solution. C) Electrolytes are enzymes that create energy in a solution. D) Electrolytes are hydrophobic and will create an electrical barrier between the hydrophobic substances and the hydrophilic substances in a solution. E) Electrolytes are sugar polymers used to rehydrate by increasing plasma volume.
B) Electrolytes are ions that will conduct an electrical current in a solution.
Describe the subatomic particle not in the nucleus. (Module 2.1C) A) Protons and neutrons are not in the nucleus. They whirl around the nucleus creating a proton and neutron cloud. B) Electrons are not in the nucleus. They whirl around the nucleus creating an electron cloud. C) Protons and electrons are not in the nucleus. They whirl around the nucleus creating a proton and electron cloud. D) Neutrons are not in the nucleus. They whirl around the nucleus creating a neutron cloud. E) Protons are not in the nucleus. They whirl around the nucleus creating a proton cloud.
B) Electrons are not in the nucleus. They whirl around the nucleus creating an electron cloud.
Describe why table salt is a compound. (Module 2.4A) A) Table salt is a compound because it is made up of only one element with different isotopes. B) Table salt is a compound because it is made up of more than one element in a fixed proportion. C) Table salt is a compound because it is made up of only one element bound with more than one type of chemical bond. D) Table salt is a compound because it is made up of more than one element in different proportions. E) Table salt is a compound because it is made up of more than one isotope in different proportions.
B) Table salt is a compound because it is made up of more than one element in a fixed proportion.
Explain why small insects can walk on the surface of a pond and why tears protect the surface of the eye from dust particles. (Module 2.5C) A) The attraction of water molecules creates a gas layer that prevents small objects from penetrating the water. B) The attraction of water molecules creates a surface tension barrier that prevents small objects from penetrating the water. C) The attraction of water molecules forms ionic bonds creating a barrier that prevents small objects from penetrating the water. D) The attraction of water molecules creates an ice layer that prevents small objects from penetrating the water. E) The attraction of the water molecules disrupts the ionic bonds preventing small objects from penetrating the water.
B) The attraction of water molecules creates a surface tension barrier that prevents small objects from penetrating the water.
In living cells, complex metabolic reactions proceed in a series of steps called A) products. B) a metabolic pathway. C) enzymes. D) reactants. E) catalysts.
B) a metabolic pathway.
In an aqueous solution, sodium ions would move toward: A) a positive terminal. B) a negative terminal. C) an organic terminal. D) a pH terminal. E) the bottom.
B) a negative terminal.
If a substance has a pH that is greater than 7, it is A) a buffer. B) alkaline. C) acidic. D) neutral. E) a salt.
B) alkaline.
All of the following are true concerning enzymes except that they A) lower the activation energy required for a reaction. B) are consumed during the reaction. C) affect only the rate of a chemical reaction. D) function as biological catalysts. E) are proteins.
B) are consumed during the reaction.
The smallest stable units of matter are: A) protons B) atoms C) electrons D) molecules E) neutrons
B) atoms
By what means are water molecules attracted to each other? (Module 2.5B) A) by ionic bonds B) by hydrogen bonds C) by nonpolar covalent bonds D) by oxygen bonds E) by isotopes
B) by hydrogen bonds
Ionic bonds are formed when A) two or more atoms lose electrons at the same time. B) electrons are completely transferred from one atom to another. C) atoms share electrons. D) hydrogen forms bonds with negatively charged atoms. E) a pair of electrons is shared unequally by two atoms.
B) electrons are completely transferred from one atom to another.
The weakest bond between two atoms is the ________ bond. A) polar B) hydrogen C) nonpolar D) covalent E) ionic
B) hydrogen
Which element commonly has only a proton as its nucleus? A) neon B) hydrogen C) helium D) argon E) None of the answers is correct.
B) hydrogen
The molecule H2 is known as: A) hydroxide. B) hydrogen. C) helium. D) hydrohydrogen. E) semi-water.
B) hydrogen.
A hydrogen ion is the same as what subatomic particle? (Module 2.12B) A) neutrino B) proton C) electron D) neutron E) quark
B) proton
Which of the following lists contains only trace elements? A) sulfur, chlorine, oxygen B) silicon, fluorine C) boron, oxygen, carbon D) selenium, hydrogen, calcium E) cobalt, calcium, sodium
B) silicon, fluorine
If one pair of electrons is unequally shared between two atoms, a ________ occurs. A) double polar covalent bond B) single polar covalent bond C) double nonpolar covalent bond D) hydrogen bond E) single nonpolar covalent bond
B) single polar covalent bond
Which of the following substances would be most acidic? A) tomato juice, pH = 4 B) stomach secretions, pH = 1 C) white wine, pH = 3 D) lemon juice, pH = 2 E) urine, pH = 6
B) stomach secretions, pH = 1
What is formula weight? (Module 2.7C) A) the total weight of an element including the isotopes B) the sum of the atomic weights of the elements making up an ionic compound C) the weight in grams equal to the element's atomic weight D) the sum of the atomic weights of its component atoms E) the average weight of an element's different atomic masses and proportions of its different isotopes
B) the sum of the atomic weights of the elements making up an ionic compound
Magnesium atoms have two electrons in the outermost shell. As a result, you would expect magnesium to form ions with a charge of: A) +1. B) -2. C) +2. D) -1. E) either +2 or -2.
C) +2.
The innermost electron shell in an atom holds up to ________ electrons. A) 1 B) 6 C) 2 D) 4 E) 8
C) 2
In the reaction listed below, what coefficient needs to be added to balance the equation? 6 CO2 + 6 H2O → C6H12O6 + ________ O2 A) 8 B) 10 C) 6 D) 4 E) 2
C) 6
If an element is composed of atoms with an atomic number of 6 and a mass number of 14, then the nucleus of a neutral atom of this element contains A) 8 electrons. B) 6 protons. C) 6 protons and 8 neutrons. D) 6 protons and 8 electrons. E) 8 neutrons.
C) 6 protons and 8 neutrons.
What is the relationship between an atom and matter? (Module 2.1A) A) An atom is the smallest stable unit of matter, and matter is a pure substance consisting only of atoms with the same atomic number. B) An atom is the largest stable unit of matter, and matter is anything that takes up space and has mass. C) An atom is the smallest stable unit of matter, and matter is anything that takes up space and has mass. D) An atom is a particle with a negative electrical charge, and matter is mass within a gravitational field. E) An atom is a chemical substance made up of two or more different elements in a fixed proportion, and matter is a pure substance consisting only of atoms with the same atomic number.
C) An atom is the smallest stable unit of matter, and matter is anything that takes up space and has mass.
Which of the following is not a cation? A) Ca2+ B) K+ C) Cl- D) Mg2+ E) Na+
C) Cl-
Compare the role of water in hydrolysis and dehydration synthesis reactions. (Module 2.8A) A) In hydrolysis, water is a product; in dehydration synthesis, water is a reactant. B) In hydrolysis and dehydration synthesis, water is a reactant. C) In hydrolysis, water is a reactant; in dehydration synthesis, water is a product. D) In hydrolysis and dehydration synthesis, water is a product. E) In hydrolysis and dehydration synthesis, water is an enzyme.
C) In hydrolysis, water is a reactant; in dehydration synthesis, water is a product.
Carbon-12 (12C) is the most common form of the element carbon. How is the isotope carbon-13 (13C) similar to and different from 12C? (Module 2.2B) A) Isotope 13C has the same chemical properties but has one more proton than 12C. B) Isotope 13C has different chemical properties and has one more electron and one more proton than 12C. C) Isotope 13C has the same chemical properties but has one more neutron than 12C. D) Isotope 13C has the same chemical properties but has one more electron than 12C. E) Isotope 13C has different chemical properties and has one more electron than 12C.
C) Isotope 13C has the same chemical properties but has one more neutron than 12C.
In chemical notation, the symbol Ca2+ means: A) a calcium ion that has gained two electrons. B) two calcium atoms. C) a calcium ion that has lost two electrons. D) a calcium ion that has lost two protons. E) a calcium ion that has gained two protons
C) a calcium ion that has lost two electrons.
Ions with a negative charge are called: A) positrons. B) polar molecules. C) anions. D) protons. E) cations.
C) anions.
The actual mass of an atom is known as its: A) mass number B) atomic number. C) atomic weight. D) element number. E) atomic mass unit.
C) atomic weight.
Nonpolar organic molecules are good examples of A) molecules that will dissociate when placed into water. B) solutes. C) hydrophobic compounds. D) hydrophilic compounds. E) electrolytes.
C) hydrophobic compounds.
Molecules that do not readily dissolve in water are called A) isophobic. B) isophilic. C) hydrophobic. D) electrolytes. E) hydrophilic.
C) hydrophobic.
H2O is an example of a(n): A) covalent formula. B) ionic formula. C) molecular formula. D) glucose molecule.
C) molecular formula.
Each of the following is an example of an inorganic compound except A) bases. B) water. C) proteins. D) salts. E) acids.
C) proteins.
The "atomic number" of an atom is determined by the number of ________ it has. A) protons + electrons B) neutrons C) protons D) electrons E) protons + neutrons
C) protons
The three familiar states of matter listed in order from the least to most thermal energy are: A) solid, gas, liquid. B) gas, solid, liquid. C) solid, liquid, gas. D) gas, liquid, solid. E) liquid, gas, solid.
C) solid, liquid, gas.
A(n) ________ is a homogeneous mixture containing a solvent and a solute. A) blend B) concoction C) solution D) inorganic molecule E) organic molecule
C) solution
Magnesium atoms have two electrons in their outermost shells, and chlorine atoms have seven. The compound magnesium chloride would contain: A) 2 magnesium and 1 chlorine. B) 1 magnesium and 1 chlorine. C) 2 magnesium and 7 chlorine. D) 1 magnesium and 2 chlorine. E) It is impossible to determine without more information.
D) 1 magnesium and 2 chlorine.
Indicate the maximum number of electrons that can occupy each of the first three energy levels of an atom. (Module 2.3A) A) 1, 2, 4 B) 2, 8, 16 C) 1, 4, 8 D) 2, 8, 8 E) 2, 4, 8
D) 2, 8, 8
What is an enzyme? (Module 2.9A) A) An enzyme is an inorganic compound. B) An enzyme is a protein that increases the activation energy so more energy can be generated. C) An enzyme is a polymer produced by linking monomers together. D) An enzyme is a protein that lowers the activation energy of a reaction. E) An enzyme provides the activation energy of a reaction.
D) An enzyme is a protein that lowers the activation energy of a reaction.
________ compounds do not usually contain carbon as a primary structural atom. A) Endergonic B) Exergonic C) Complex D) Inorganic E) Organic
D) Inorganic
List the chemical symbols of the six most abundant elements in the human body and their total percentage contribution to total body weight. (Module 2.2E) A) O, C, H, N, K, Na. They account for 99.3% of total body weight. B) O, C, H, N, Ca, and P. They account for 100% of total body weight. C) O, C, H, N, K, Na. They account for 65% of total body weight. D) O, C, H, N, Ca, and P. They account for 99.3% of total body weight. E) O, C, H, N, Ca, and P. They account for 65% of total body weight.
D) O, C, H, N, Ca, and P. They account for 99.3% of total body weight.
The gravitational field of the moon is 17% of Earth's. How would the weight and mass of a 100-pound astronaut change on the moon? (Module 2.1D) A) On the moon, the astronaut would have less mass than on Earth and would weigh 17 pounds (100 × 0.17). B) On the moon, the astronaut would have the same mass as on Earth but would weigh 588 pounds (100/0.17). C) On the moon, the astronaut would have more mass than on Earth but would weigh the same. D) On the moon, the astronaut would have the same mass as on Earth but would weigh 17 pounds (100 × 0.17). E) On the moon, the astronaut would have less mass than on Earth but would weigh the same.
D) On the moon, the astronaut would have the same mass as on Earth but would weigh 17 pounds (100 × 0.17).
________ molecules are compounds that contain carbon as the primary structural atom. A) Exergonic B) Inorganic C) Endergonic D) Organic E) Complex
D) Organic
Describe the different states of matter in terms of shape and volume. (Module 2.5A) A) Solids have a fixed volume and shape, liquids have neither a constant volume nor a fixed shape, and gases have a constant volume but no fixed shape. B) Solids have a constant volume but not fixed shape, liquids have neither a constant volume nor a fixed shape, and gases have a fixed volume and shape. C) Solids have neither a constant volume nor a fixed shape, liquids have a constant volume but no fixed shape, and gases have a fixed volume and shape. D) Solids have a fixed volume and shape, liquids have a constant volume but no fixed shape, and gases have neither a constant volume nor a fixed shape. E) Solids have a constant volume but not fixed shape, liquids have a fixed volume and shape, and gases have neither a constant volume nor a fixed shape.
D) Solids have a fixed volume and shape, liquids have a constant volume but no fixed shape, and gases have neither a constant volume nor a fixed shape.
Cations are smaller in diameter than their electrically neutral atom. Why? (Module 2.3D) A) When electrons are gained, the electrons are pulled closer toward the nucleus. B) When electrons are lost, the remaining electrons enter the nucleus. C) When electrons are lost, the remaining electrons are pulled further away from the nucleus. D) When electrons are lost, the remaining electrons are pulled closer toward the nucleus. E) When electrons are gained, the electrons are pulled further away from the nucleus.
D) When electrons are lost, the remaining electrons are pulled closer toward the nucleus.
Elements that have atoms with full outer shells of electrons: A) will normally form anions. B) will normally form cations. C) will form many compounds. D) are inert gases. E) frequently form hydrogen bonds.
D) are inert gases.
When atoms complete their outer electron shell by sharing electrons, they form A) ionic bonds. B) cations. C) hydrogen bonds. D) covalent bonds. E) anions.
D) covalent bonds.
A(n) ________ is a pure substance composed of atoms. A) electron B) compound C) molecule D) element E) neutron
D) element
The reaction A + B + energy → AB is an example of a(n) A) exchange reaction. B) decomposition reaction. C) equilibrium reaction. D) endergonic reaction. E) exergonic reaction.
D) endergonic reaction.
Chemical reactions that release energy are called A) metabolic. B) endergonic. C) energetic. D) exergonic. E) enzymatic.
D) exergonic.
Chemical reactions that yield energy, such as heat, are said to be A) endergonic. B) thermonuclear. C) activated. D) exergonic. E) neutral.
D) exergonic.
Compounds that can be synthesized or broken down by chemical reactions inside the body are called A) inorganic compounds. B) nutrients. C) organic compounds. D) metabolites. E) enzymes.
D) metabolites.
The center of an atom is called the: A) electron cloud. B) molecule. C) element. D) nucleus. E) proton.
D) nucleus.
The chemical behavior of an atom is determined by the: A) number of neutrons. B) size of the atom. C) mass of the nucleus. D) outermost electron shell. E) number of protons.
D) outermost electron shell.
By weight, which element is the most plentiful in the human body? A) carbon B) potassium C) sodium D) oxygen E) sulfur
D) oxygen
The mass number represents the number of: A) neutrons in an atom. B) protons in an atom. C) electrons in an ion. D) protons + neutrons. E) neutrons + electrons.
D) protons + neutrons.
AB → A + B is to decomposition as A + B → AB is to A) metabolism. B) replacement. C) exchange. D) synthesis. E) combustion.
D) synthesis.
Which property of water helps keep body temperature stabilized? A) reactivity B) surface tension C lubrication D) thermal inertia E) kinetic energy kinetic energy
D) thermal inertia
Explain why the atoms of inert elements do not react with one another or combine with atoms of other elements. (Module 2.3B) A) Atoms of inert elements are nonreactive because the outermost electron shell (valence shell) contains the minimum number of electrons possible. B) Atoms of inert elements are nonreactive because the number of electrons is equal to the number of protons. C) Atoms of inert elements are nonreactive because the innermost electron shell contains the minimum number of electrons possible. D) Atoms of inert elements are nonreactive because the innermost electron shell contains the maximum number of electrons possible. E) Atoms of inert elements are nonreactive because the outermost electron shell (valence shell) contains the maximum number of electrons possible.
E) Atoms of inert elements are nonreactive because the outermost electron shell (valence shell) contains the maximum number of electrons possible.
________ are soluble inorganic compounds whose solutions will conduct an electric current. A) Enzymes B) Ions C) Proteins D) Lipids E) Electrolytes
E) Electrolytes
Which of the following statements about hydrogen bonds is false? A) Hydrogen bonds are important for holding large molecules together. B) Hydrogen bonds can form between neighboring molecules. C) Hydrogen bonds are responsible for many of the properties of water. D) Hydrogen bonds can occur within a single molecule. E) Hydrogen bonds are strong attractive forces between hydrogen atoms and negatively charged atoms.
E) Hydrogen bonds are strong attractive forces between hydrogen atoms and negatively charged atoms.
Distinguish between hydrophilic and hydrophobic molecules. (Module 2.11C) A) Hydrophilic molecules are inorganic, whereas hydrophobic molecules are organic. B) Hydrophilic molecules do not interact with water molecules, whereas hydrophobic molecules are attracted to water. C) Hydrophilic molecules are monomers, whereas hydrophobic molecules are polymers. D) Hydrophilic molecules are organic, whereas hydrophobic molecules are inorganic. E) Hydrophilic molecules are attracted to water, whereas hydrophobic molecules do not interact with water molecules.
E) Hydrophilic molecules are attracted to water, whereas hydrophobic molecules do not interact with water molecules.
How are chemical reactions represented? (Module 2.7B) A) Reactions are represented by Lewis structural models and the total number of atoms represents the direction of the reaction. B) Reactions are represented by a sine wave and the slope represents the direction of the reaction. C) Reactions are represented by superscripts and subscripts and the charge represents the direction of the reaction. D) Reactions are represented by line plots and the line represents the direction of the reaction. E) Reactions are represented by chemical equations and the arrow represents the direction of the reaction.
E) Reactions are represented by chemical equations and the arrow represents the direction of the reaction.
What is the source of energy that converts glucose, a six-carbon molecule, into two three-carbon molecules in cells? (Module 2.8C) A) The kinetic energy is converted to potential energy as the glucose molecule forms. B) The kinetic energy released as ions are formed when glucose is broken down. C) The potential energy stored in the ionic bonds of the glucose molecule is released when some of the bonds break. D) The kinetic energy released as one glucose molecule combines with another glucose molecule. E) The potential energy stored in the covalent bonds of the glucose molecule is released when some of the bonds break.
E) The potential energy stored in the covalent bonds of the glucose molecule is released when some of the bonds break.
Which of the following is/are inorganic substance(s)? A) carbon dioxide B) glycerol C) fructose D) water E) both water and carbon dioxide
E) both water and carbon dioxide
The molecule CO2 is known as: A) carbonized oxygen. B) carbonated oxygen. C) carbon monoxide. D) carbon oxide. E) carbon dioxide.
E) carbon dioxide.
Oxygen is required in biological systems for: A) serving as a structural component of bone. B) serving as a catalyst. C) chemical messengers. D) storage of energy. E) cellular respiration.
E) cellular respiration.
Chemical reactions that absorb energy are called A) metabolic. B) energetic. C) enzymatic. D) exergonic. E) endergonic.
E) endergonic.
Oppositely charged ions in solution are prevented from combining by A) water's nonpolar nature. B) heat capacity of water. C) hydrogen bonding. D) free radicals. E) hydration spheres.
E) hydration spheres.
Atoms of the same element whose nuclei contain the same number of protons, but different numbers of neutrons, are called A) principal elements. B) ions. C) trace elements. D) isomers. E) isotopes.
E) isotopes.
In dehydration reactions, compounds A) gain electrons. B) gain water molecules. C) convert water molecules to hydrogen and oxygen. D) convert hydrogen and oxygen to water. E) lose water molecules.
E) lose water molecules.
Explain how the ionic compound sodium chloride dissolves in water. (Module 2.11A) A) Sodium chloride is hydrophobic so it does not dissolve in water. B) The positive poles of water molecules are attracted to the positively charged chloride ions, and the negative poles of water molecules are attracted to the negatively charged sodium ions. C) The negative poles of water molecules are attracted to the positively charged chloride ions, and the positive poles of water molecules are attracted to the negatively charged sodium ions. D) The negative poles of water molecules are attracted to the negatively charged chloride ions, and the positive poles of water molecules are attracted to the positively charged sodium ions. E) positive poles of water molecules are attracted to the negatively charged chloride ions, and the negative poles of water molecules are attracted to the positively charged sodium ions.
E) positive poles of water molecules are attracted to the negatively charged chloride ions, and the negative poles of water
Kinetic energy is stored as ________ energy when a spring is stretched. A) motion B) work C) thermal D) chemical E) potential
E) potential
A dust particle floating on a water surface illustrates A) static electricity. B) chemical tension. C) hydrophilic attraction. D) heat capacity. E) surface tension.
E) surface tension
The reaction N2 + 3 H2 → 2 NH3 is an example of a(n) A) exchange reaction. B) enzyme reaction. C) decomposition reaction. D) metabolic reaction. E) synthesis reaction
E) synthesis reaction
