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Flashcards in Chapter 2 Deck (209):
1

Proton

positively-charged subatomic particle

2

center of an atom that contains protons and neutrons

nucleus

(chemistry)

3

substance made up of atoms of more than one element

compound

4

bond between charged ions

Ionic Bond

5

positively-charged subatomic particle

Proton

6

Base

substance that can accept hydrogen ion in solution

7

heat of vaporization

energy required to convert liquid to a gas

8

solution

solvent and dissolved solute mixture

9

hydrophobic

uncharged, nonpolar groups of atoms/molecules that have no affinity for water

10

  • measure of a solution's acidity/hydrogen ion concentration
  • -log( [H+] )

pH

11

hydrophillic

having an affinity for water; polar

12

anion

negatively charged ion

13

energy

capacity to do work or to accomplish change in physical or chemical systems

14

orbital

region in space surrounding nucleus in which an electron is most likely to be found

15

acid

substance that can release a proton in solution

16

polar

having opposite electric charges at two ends

17

molecule

chemical substance consisting of two or more atoms joined by bonds or attractions

18

reactant

substance that enters into a chemical reaction

19

solvent

liquid in which solutes are dissolved to form a solution

20

Molecular Weight

sum of atomic weights in a molecule

21

electron

(def)

negatively charged subatomic particle

22

hydrogen bond

weak electrostatic bond between slightly-positive hydrogen atom and slightly-negative charge on a nearby atom

23

ion

electrically charged particle that forms when atom gains or loses electron(s)

24

van der Waals forces

weak attractions between atoms resulting from interactions between electons of one atom and the nucleus of another

25

van der Waals forces

(strength)

bonds that are about 1/4 as strong as hydrogen bonds

26

neuton

  • neutrally-charged subatomic particle located in the nuclei of atoms
  • molecular weight of approx. 1 amu

27

reversible reaction

chemical change that can occur in both forward and reverse direction

28

electron shell

region in which electrons orbit; surrounding atomic nucleus at fixed energy level

29

sum of an atom's protons and neutrons

mass number

30

radioisotope

radioactive isotope

(e.g. carbon-14, hydrogen-3, tritium)

31

substance that can accept or release hydrogen ions to resist changes in pH

buffer

32

amount of energy required to raise 1 gram of a substance by 1 deg C

specific heat

33

isotope

atom containing same number of protons as shown in the periodic table, but differing in the number of neutrons within the nucleus

34

specific heat

amount of energy required to raise 1 gram of a substance by 1 deg C

35

compound

substance made up of atoms of more than one element

36

cohesion

tendency of molecules to stick together

37

element

substance that cannot be converted to a simpler substance

38

atomic number

  • equivalent to the number of protons in an atom's nucleus (equal to electrons around atom)
  • determines chemical properties of atom

39

electronegativity

affinity of an atom to attract electrons when it occurs as part of a compound

40

mole

avogadro's number of something

41

covalent bond

bond based on the (equal or unequal) sharing of electrons between two atoms

42

avogadro's number

6.022 x 10^23

43

chemical bond

attractive force linking two atoms

44

pH

  • measure of a solution's acidity/hydrogen ion concentration
  • -log( [H+] )

45

buffer

substance that can accept or release hydrogen ions to resist changes in pH

46

nucleus

(chemistry)

center of an atom that contains protons and neutrons

47

substance that can accept hydrogen ion in solution

Base

48

energy required to convert liquid to a gas

heat of vaporization

49

solvent and dissolved solute mixture

solution

50

uncharged, nonpolar groups of atoms/molecules that have no affinity for water

hydrophobic

51

radioactive isotope

(e.g. carbon-14, hydrogen-3, tritium)

radioisotope

52

solute

substance dissolved in a liquid to form a solution

53

mass number

sum of an atom's protons and neutrons

54

having an affinity for water; polar

hydrophillic

55

negatively charged ion

anion

56

Ionic Bond

bond between charged ions

57

capacity to do work or to accomplish change in physical or chemical systems

energy

58

region in space surrounding nucleus in which an electron is most likely to be found

orbital

59

tendency of molecules to stick together

cohesion

60

substance that can release a proton in solution

acid

61

having opposite electric charges at two ends

polar

62

substance that cannot be converted to a simpler substance

element

63

chemical substance consisting of two or more atoms joined by bonds or attractions

molecule

64

substance that enters into a chemical reaction

reactant

65

  • equivalent to the number of protons in an atom's nucleus (equal to electrons around atom)
  • determines chemical properties of atom

atomic number

66

liquid in which solutes are dissolved to form a solution

solvent

67

substance dissolved in a liquid to form a solution

solute

68

affinity of an atom to attract electrons when it occurs as part of a compound

electronegativity

69

sum of atomic weights in a molecule

Molecular Weight

70

avogadro's number of something

mole

71

negatively charged subatomic particle

electron

(def)

72

bond based on the (equal or unequal) sharing of electrons between two atoms

covalent bond

73

weak electrostatic bond between slightly-positive hydrogen atom and slightly-negative charge on a nearby atom

hydrogen bond

74

positively charged ion

cation

75

electrically charged particle that forms when atom gains or loses electron(s)

ion

76

6.022 x 10^23

avogadro's number

77

weak attractions between atoms resulting from interactions between electons of one atom and the nucleus of another

van der Waals forces

78

attractive force linking two atoms

chemical bond

79

bonds that are about 1/4 as strong as hydrogen bonds

van der Waals forces

(strength)

80

  • neutrally-charged subatomic particle located in the nuclei of atoms
  • molecular weight of approx. 1 amu

neuton

81

cation

positively charged ion

82

chemical change that can occur in both forward and reverse direction

reversible reaction

83

region in which electrons orbit; surrounding atomic nucleus at fixed energy level

electron shell

84

the (weighted) average mass numbers of a sample of atoms

atomic weight

85

atom containing same number of protons as shown in the periodic table, but differing in the number of neutrons within the nucleus

isotope

86

atomic weight

the (weighted) average mass numbers of a sample of atoms

87

Phosphorus has an atomic number of 15 and an atomic mass of 31. How many neutrons does phosphorus have?

A. 5
B. 16
C. 30
D. 31
E.  47

B

88

Particles having a net negative charge are called

A. electronegative
B. cations
C. anions
D. acids
E. bases

C

89

Which of the following correctly states an unusual property of water?

A. Water will not react with other atoms
B. Water's solid state is denser than its liquid state.
C. Energy is not required to change water from a wolid to a liquid.
D. Little heat energy is needed to raise the temperature of water.
E.  The hydrogen bonds between water molecules continually form and break.

E

90

Polar molecules

A. have bonds with an overall positive charge.
B. have bonds with an unequal distribution of electric charge.
C. must form ions in water solution.
D. have bonds with an equal distribution of electrical charge.
E.  have bonds with an overall negative charge.

B

91

Covalent bond formation depends ont eh ability of atoms to

A. share electrons with other atoms.
B. donate electrons to other atoms.
C. receive electrons from other atoms.
D. both a and b
E.  all of the above

A

92

The element with which of the following atomic numbers would be most stable?

A. 1
B. 3
C. 12
D. 15
E. 18

E

93

The role of a buffer is to

A. allow the pH of a solution to vary widely.
B. make a solution basic.
C. maintain pH homeostasis.
D. disrupt pH homeostasis.
E.  make a solution more acidic.

C

94

Based on the symbol for iron (Fe) shown here, select the correct list of characteristics for iron.

A. Number of protons = 26; number of electrons = 29; number of neutrons = 29
B. Number of protons = 29; number of electrons = 26; number of neutrons = 26
C. Number of protons = 26; number of electrons = 26; number of neutrons = 55
D. Number of protons = 26; number of electrons = 26; number of neutrons = 29
E. Number of protons = 55; number of electrons = 55; number of neutrons = 26 

Q image thumb

D

95

The graph shown depicts a pH scale with the pH values of several substances indicated. Which of the following statements is false?

A. Distilled water (pH 7.0) has an equal concentration of H+ and OH– ions.
B. Baking soda (pH 9.0) has a higher concentration of H+ ions than black coffee (pH 5.0).
C. Milk of magnesia (pH 10.0) has a higher concentration of OH– ions than seawater (pH 8.0)
D. A solution with a lower pH has a higher concentration of H+ ions than a solution with a higher pH.
E. A solution with a higher pH has a higher concentration of OH– ions than a solution with a lower pH. 

B

96

Which example shown (A–E) depicts the correct distribution of charge and hydrogen bonding between two water molecules?

A
B
C
D
E

Q image thumb

A

97

The accompanying figure demonstrates the process of salt dissolving in water. Which of the following is not depicted?

A. Cations and anions
B. Ionic bonding
C. Hydrogen bonding
D. Solute dissolving in water
E. Hydrophobic interactions 

E

98

In comparing solid water (ice) and liquid water, select the false statement from the following choices.

A. Liquid water is less dense than solid water.
B. Solid water has a crystalline structure.
C. Hydrogen bonds hold water molecules in a rigid state in solid water.
D. In solid water, each water molecule can be hydrogen-bonded to four other water molecules.
E. Hydrogen bonds continue to break and re-form in liquid water. 

A

99

Consider the accompanying figure showing a hydrogen bond between two water molecules. Which of the following properties of water is not caused by this interaction?

A. High surface tension
B. Great cohesive strength
C. Low specific heat
D. Excellence as a solvent
E. High heat of evaporation 

Q image thumb

C

99

Consider the carbonic acid (H2CO3) buffer system depicted in the graph shown. In this system, the following reaction (H2CO3 → HCO3– + H+) is utilized to reduce the effect of adding acid. From the following choices, select the one that makes the following statement true: In this buffer system, HCO3– is _______, H2CO3 is _______, and _______ would predominate in the system, receiving zero units of base.

A. a base; an acid; HCO3–
B. a base; an acid; H2CO3
C. an acid; a base; HCO3–
D. an acid; a base; H2CO3
E. basic; acidic; H2CO3 

Q image thumb

100

This figure shows the radioisotope tritium. Which of the following statements regarding radioisotopes is false?

A. Radioisotopes differ from other isotopes in that they give off energy.
B. Radioisotopes can be used as a molecular “tag” for medical diagnostic purposes.
C. Radioisotopes are unstable because they contain more protons than nonradioactive forms of the same element.
D. Radioisotopes can be damaging to cells.
E. During the process of radioactive decay, radioisotopes can release energy in the form of alpha radiation. 

Q image thumb

C

101

The part of the atom that determines how the atom behaves chemically is the

A. proton.
B. election.
C. neutron.
D. innermost shell.
E. nucleus.

B

103

Which of the following statements about chemcial reactions is false?

A. They occur when atoms combine or change their bonding partners.
B. Reactions may go to completion.
C. The products of a chemica reaction are formed from the reactants.
D. Energy may be created or destroyed in a chemical reaction.
E. Changes in forms of energy may accompany chemical reactions.

D

104

Refer to the periodic table. Which of the following has the same number of outer-shell (valence) electrons as oxygen?

A. S
B. N
C. F
D. Na
E. Ca

A

105

Covalent Bonds: Given the shell configurations of hydrogen, carbon, and sulfur (shown), select a molecule from the list below that could not be formed

A. CH4
B. H–C=C–H
C. H3C–CH3
D. H–S–H
E. S=S 

Q image thumb

B

106

Oxygen forms ___ covalent bond(s), carbon forms ___, and hydrogen forms ___.

A. 1, 4, 1
B. 4, 4, 4
C. 2, 4, 0
D. 2, 4, 1
E. 2, 2, 2

D

107

The four most common elements in organisms are

A.  Ca, Fe, H, O
B.  H2O, C, H, O
C.  C, O, H, N
D.  N, C, Fe, H
E.  P, H2O, C, O

C

108

Atomic and Mass Numbers I: This figure shows an atom of helium. Which of the following characteristics is true for helium?

A. Mass number = 4; atomic number = 2; net charge = 0
B. Mass number = 4; atomic number = 4; net charge = 0
C. Mass number = 4; atomic number = 2; net charge = +2
D. Mass number = 6; atomic number = 2; net charge = 0
E. Mass number = 6; atomic number = 2; net charge = +1 

Q image thumb

A

109

Chemical Reactions: Which of the following statements about the chemical reaction in the figure shown is false?

A. The reactants are to the left of the arrow.
B. The arrow represents the direction of the chemical reaction.
C. There is more potential chemical energy in the products than in the reactants.
D. The energy associated with this reaction could be measured in calories.
E. The difference in potential chemical energy in this reaction is released as heat and light. 

Q image thumb

C

110

A basic solution contains

A. more OH- ions than H+ ions.
B. more H+ ions than OH- ions.
C. the same number of OH- ions and H+ ions.
D. no OH- ions.
E. none of the above

A

111

Ions: Given the electron shell configuration and mass and atomic numbers for the sodium ion (Na+) shown here, select the correct choice below to complete the following sentence: The sodium ion has _______ protons in its nucleus, _______ electrons in its outermost shell, and it is a(n) _______.

A. 10; 0; anion
B. 11; 8; anion
C. 11; 0; anion
D. 10; 0; cation
E. 11; 8; cation 

E

112

Given the electron shell configuration for sulfur (S) shown, select the correct choice below to complete the following sentence: Sulfur has _______ protons in its nucleus and requires _______ more electrons to complete its outer shell.

A. 8; 2
B. 8; 6
C. 16; 2
D. 16; 6
E. 16; 8 

Q image thumb

C

113

What determines if a molecule is polar, nonpolar, or ionic?

A. the number of protons
B. the bond distances
C. the differences in the electronegativities of the atoms
D. the ionic charges
E. the distance of the electrons from the nucleus

C

114

The three most abundant elements in a human skin cell are

A. calcium, carbon, and oxygen.
B. carbon, hydrogen, and oxygen.
C. carbon, hydrogen, and sodium.
D. carbon, nitrogen, and potassium.
E. nitrogen, hydrogen, and argon. 

B

115

Which of the following statements about the isotopes of an element is not true?

A. They all have the same atomic number.
B. They all have the same number of protons.
C. They all have the same number of neutrons.
D. They all have the same number of electrons.
E. They all have identical chemical properties. 

C

116

The atomic weight (atomic mass) of an element

A. equals the number of neutrons in an atom.
B. equals the number of protons in an atom.
C. equals the number of electrons in an atom.
D. equals the number of neutrons plus the number of protons.
E. depends on the relative abundances of its electrons and neutrons. 

D

117

The atomic number of an element

A. equals the number of neutrons in an atom.
B. equals the number of protons in an atom.
C. equals the number of protons minus the number of neutrons.
D. equals the number of neutrons plus the number of protons.
E. depends on the isotope. 

B

118

When table salt (NaCl) is added to water,

A. a covalent bond is broken.
B. an acidic solution is formed.
C. the Na+ and Cl− ions are separated.
D. the Na+ ions are attracted to the hydrogen atoms of water.
E. water molecules surround the Na+ (but not Cl−) ions. 

C

119

Hydrophobic interactions

A. are stronger than hydrogen bonds.
B. are stronger than covalent bonds.
C. can hold two ions together.
D. can hold two nonpolar molecules together.
E. are responsible for the surface tension of water. 

D

121

The reaction HCl → H+ + Cl− in the human stomach is an example of the

A. cleavage of a hydrophobic bond.
B. formation of a hydrogen bond.
C. elevation of the pH of the stomach.
D. formation of ions by dissolving an acid.
E. formation of polar covalent bonds. 

D

122

Which of the following statements about water is not true?

A. It releases a large amount of heat when changing from liquid into vapor.
B. Its solid form is less dense than its liquid form.
C. It is the most effective solvent for polar molecules.
D. It is typically the most abundant substance in a living organism.
E. It takes part in some important chemical reactions. 

A

123

The hydrogen bond between two water molecules arises because water is

A. polar.
B. nonpolar.
C. a liquid.
D. small.
E. hydrophobic

A

124

Which of the following statements about covalent bonds is not true?

A. A covalent bond is stronger than a hydrogen bond.
B. A covalent bond can form between atoms of the same element.
Cc. Only a single covalent bond can form between two atoms.
D. A covalent bond results from the sharing of electrons by two atoms.
E. A covalent bond can form between atoms of different elements. 

C

125

positively-charged subatomic particle

Proton

126

nucleus

(chemistry)

center of an atom that contains protons and neutrons

127

compound

substance made up of atoms of more than one element

128

Ionic Bond

bond between charged ions

129

Proton

positively-charged subatomic particle

130

substance that can accept hydrogen ion in solution

Base

131

energy required to convert liquid to a gas

heat of vaporization

132

solvent and dissolved solute mixture

solution

133

uncharged, nonpolar groups of atoms/molecules that have no affinity for water

hydrophobic

134

pH

  • measure of a solution's acidity/hydrogen ion concentration
  • -log( [H+] )

135

having an affinity for water; polar

hydrophillic

136

negatively charged ion

anion

137

capacity to do work or to accomplish change in physical or chemical systems

energy

138

region in space surrounding nucleus in which an electron is most likely to be found

orbital

139

substance that can release a proton in solution

acid

140

having opposite electric charges at two ends

polar

141

chemical substance consisting of two or more atoms joined by bonds or attractions

molecule

142

substance that enters into a chemical reaction

reactant

143

liquid in which solutes are dissolved to form a solution

solvent

144

sum of atomic weights in a molecule

Molecular Weight

145

negatively charged subatomic particle

electron

(def)

146

weak electrostatic bond between slightly-positive hydrogen atom and slightly-negative charge on a nearby atom

hydrogen bond

147

electrically charged particle that forms when atom gains or loses electron(s)

ion

148

weak attractions between atoms resulting from interactions between electons of one atom and the nucleus of another

van der Waals forces

149

bonds that are about 1/4 as strong as hydrogen bonds

van der Waals forces

(strength)

150

  • neutrally-charged subatomic particle located in the nuclei of atoms
  • molecular weight of approx. 1 amu

neuton

151

chemical change that can occur in both forward and reverse direction

reversible reaction

152

region in which electrons orbit; surrounding atomic nucleus at fixed energy level

electron shell

153

mass number

sum of an atom's protons and neutrons

154

radioactive isotope

(e.g. carbon-14, hydrogen-3, tritium)

radioisotope

155

buffer

substance that can accept or release hydrogen ions to resist changes in pH

156

specific heat

amount of energy required to raise 1 gram of a substance by 1 deg C

157

atom containing same number of protons as shown in the periodic table, but differing in the number of neutrons within the nucleus

isotope

158

amount of energy required to raise 1 gram of a substance by 1 deg C

specific heat

159

substance made up of atoms of more than one element

compound

160

tendency of molecules to stick together

cohesion

161

substance that cannot be converted to a simpler substance

element

162

  • equivalent to the number of protons in an atom's nucleus (equal to electrons around atom)
  • determines chemical properties of atom

atomic number

163

affinity of an atom to attract electrons when it occurs as part of a compound

electronegativity

164

avogadro's number of something

mole

165

bond based on the (equal or unequal) sharing of electrons between two atoms

covalent bond

166

6.022 x 10^23

avogadro's number

167

attractive force linking two atoms

chemical bond

168

  • measure of a solution's acidity/hydrogen ion concentration
  • -log( [H+] )

pH

169

substance that can accept or release hydrogen ions to resist changes in pH

buffer

170

center of an atom that contains protons and neutrons

nucleus

(chemistry)

171

Base

substance that can accept hydrogen ion in solution

172

heat of vaporization

energy required to convert liquid to a gas

173

solution

solvent and dissolved solute mixture

174

hydrophobic

uncharged, nonpolar groups of atoms/molecules that have no affinity for water

175

radioisotope

radioactive isotope

(e.g. carbon-14, hydrogen-3, tritium)

176

substance dissolved in a liquid to form a solution

solute

177

sum of an atom's protons and neutrons

mass number

178

hydrophillic

having an affinity for water; polar

179

anion

negatively charged ion

180

bond between charged ions

Ionic Bond

181

energy

capacity to do work or to accomplish change in physical or chemical systems

182

orbital

region in space surrounding nucleus in which an electron is most likely to be found

183

cohesion

tendency of molecules to stick together

184

acid

substance that can release a proton in solution

185

polar

having opposite electric charges at two ends

186

element

substance that cannot be converted to a simpler substance

187

molecule

chemical substance consisting of two or more atoms joined by bonds or attractions

188

reactant

substance that enters into a chemical reaction

189

atomic number

  • equivalent to the number of protons in an atom's nucleus (equal to electrons around atom)
  • determines chemical properties of atom

190

solvent

liquid in which solutes are dissolved to form a solution

191

solute

substance dissolved in a liquid to form a solution

192

electronegativity

affinity of an atom to attract electrons when it occurs as part of a compound

193

Molecular Weight

sum of atomic weights in a molecule

194

mole

avogadro's number of something

195

electron

(def)

negatively charged subatomic particle

196

covalent bond

bond based on the (equal or unequal) sharing of electrons between two atoms

197

hydrogen bond

weak electrostatic bond between slightly-positive hydrogen atom and slightly-negative charge on a nearby atom

198

cation

positively charged ion

199

ion

electrically charged particle that forms when atom gains or loses electron(s)

200

avogadro's number

6.022 x 10^23

201

van der Waals forces

weak attractions between atoms resulting from interactions between electons of one atom and the nucleus of another

202

chemical bond

attractive force linking two atoms

203

van der Waals forces

(strength)

bonds that are about 1/4 as strong as hydrogen bonds

204

neuton

  • neutrally-charged subatomic particle located in the nuclei of atoms
  • molecular weight of approx. 1 amu

205

positively charged ion

cation

206

reversible reaction

chemical change that can occur in both forward and reverse direction

207

electron shell

region in which electrons orbit; surrounding atomic nucleus at fixed energy level

208

atomic weight

the (weighted) average mass numbers of a sample of atoms

209

isotope

atom containing same number of protons as shown in the periodic table, but differing in the number of neutrons within the nucleus

210

the (weighted) average mass numbers of a sample of atoms

atomic weight