Question 1

What does HOH represent?

Accepted Answer

A) an atom of water 
B) a mixture including water 
C) a molecule of water 
D) ionic bonding of water 
A) an atom of water 
B) a mixture including water 
C) a molecule of water 
D) ionic bonding of water

Question 2

The fact that salt dissolves in water is BEST explained by the:

Accepted Answer

A) slightly charged nature of water molecules. 
B) polar nature of water molecules. 
C) hydrophobic nature of salt. 
D) ionic nature of water molecules. 
E) hydrophobic nature of the water. 
A) slightly charged nature of water molecules. 
B) polar nature of water molecules. 
C) hydrophobic nature of salt. 
D) ionic nature of water molecules. 
E) hydrophobic nature of the water.

Question 3

Most biological molecules are joined by:

Accepted Answer

A) peptide bonds. 
B) ionic bonds. 
C) hydrogen bonds. 
D) disulfide bonds. 
E) covalent bonds. 
A) peptide bonds. 
B) ionic bonds. 
C) hydrogen bonds. 
D) disulfide bonds. 
E) covalent bonds.

Question 4

The atomic number of an atom is defined as the:

Accepted Answer

A) number of electrons in the outermost energy level. 
B) total number of energy shells. 
C) arrangement of neutrons in the atomic nucleus. 
D) number of protons in the atomic nucleus. 
E) total number of electrons and neutrons. 
A) number of electrons in the outermost energy level. 
B) total number of energy shells. 
C) arrangement of neutrons in the atomic nucleus. 
D) number of protons in the atomic nucleus. 
E) total number of electrons and neutrons.

Question 5

Water molecules are cohesive because they:

Accepted Answer

A) create surface tension. 
B) form hydrogen bonds. 
C) contain protons. 
D) stick to other polar molecules. 
E) are repelled by nonpolar molecules. 
A) create surface tension. 
B) form hydrogen bonds. 
C) contain protons. 
D) stick to other polar molecules. 
E) are repelled by nonpolar molecules.

Question 6

Phosphorus has an atomic number of 15, so what is the distribution of its electrons?

Accepted Answer

A) The first energy level has eight and the second has seven. 
B) The first energy level has two, the second has eight, and the third has five. 
C) The first energy level has two and the second has 13. 
D) The first, second, and third energy levels have five electrons each. 
E) The electron arrangement cannot be determined from the atomic number alone. 
A) The first energy level has eight and the second has seven. 
B) The first energy level has two, the second has eight, and the third has five. 
C) The first energy level has two and the second has 13. 
D) The first, second, and third energy levels have five electrons each. 
E) The electron arrangement cannot be determined from the atomic number alone.

Question 7

What is the difference between covalent and ionic bonds?

Accepted Answer

Covalent bonds are the sharing

Question 8

Which of the following could potentially be a free radical?

Accepted Answer

A) oxygen (atomic number 8) 
B) helium (atomic number 2) 
C) neon (atomic number 10) 
A) oxygen (atomic number 8) 
B) helium (atomic number 2) 
C) neon (atomic number 10)

Question 9

If a substance measures 7 on the pH scale, that substance:

Accepted Answer

A) has equal concentrations of H+ and OH- ions. 
B) may be lemon juice. 
C) has a higher concentration of OH- than H+ ions. 
D) probably lacks OH- ions. 
E) is basic. 
A) has equal concentrations of H+ and OH- ions. 
B) may be lemon juice. 
C) has a higher concentration of OH- than H+ ions. 
D) probably lacks OH- ions. 
E) is basic.

Question 10

Which of the following is attracted to the hydrogen "end" of a water molecule, as depicted in this figure?

Accepted Answer

A) NaCl 
B) H 
C) Cl- 
D) Na+ 
A) NaCl 
B) H 
C) Cl- 
D) Na+

Question 11

The human body must maintain a constant pH. In the blood, bicarbonate serves as a(n)________ to help maintain the necessary pH.

Accepted Answer

A) acid 
B) buffer 
C) base 
D) solvent 
A) acid 
B) buffer 
C) base 
D) solvent

Question 12

How do buffers work?

Accepted Answer

A) They soak up extra acid and base. 
B) They accept or release H+. 
C) They accept or release OH- . 
D) They convert H+ and OH- to water. 
E) They monitor the blood pH. 
A) They soak up extra acid and base. 
B) They accept or release H+. 
C) They accept or release OH- . 
D) They convert H+ and OH- to water. 
E) They monitor the blood pH.

Question 13

Which of the following pairs has the most similar chemical properties?

Accepted Answer

A) 1H and 22Na 
B) 12C and 28Si 
C) 16O and 32S 
D) 12C and 14C 
E) 1H and 2He 
A) 1H and 22Na 
B) 12C and 28Si 
C) 16O and 32S 
D) 12C and 14C 
E) 1H and 2He

Question 14

Which four elements make up approximately 96% of living matter?

Accepted Answer

A) carbon, hydrogen, nitrogen, oxygen 
B) carbon, sulfur, phosphorus, hydrogen 
C) carbon, sodium, chlorine, magnesium 
D) carbon, oxygen, sulfur, calcium 
E) oxygen, hydrogen, calcium, sodium 
A) carbon, hydrogen, nitrogen, oxygen 
B) carbon, sulfur, phosphorus, hydrogen 
C) carbon, sodium, chlorine, magnesium 
D) carbon, oxygen, sulfur, calcium 
E) oxygen, hydrogen, calcium, sodium

Question 15

Sulfur is an essential element in the human body, and studying its characteristics is important in understanding human physiology. Sulfur atoms have six electrons in their outer shell. Based on this information, which of the following is true?

Accepted Answer

A) Sulfur can form important molecules using covalent bonds. 
B) Sulfur is inert. 
C) Sulfur is an important isotope of hydrogen. 
D) Sulfur has eight electrons in its outer shell. 
A) Sulfur can form important molecules using covalent bonds. 
B) Sulfur is inert. 
C) Sulfur is an important isotope of hydrogen. 
D) Sulfur has eight electrons in its outer shell.

Question 16

An atom of nitrogen attracts electrons more strongly than an atom of hydrogen. Which of the following BEST describes ammonia (NH3)?

Accepted Answer

A) The nitrogen is more slightly positive. 
B) The nitrogen is strongly negative. 
C) The hydrogens are more slightly positive. 
D) The hydrogens are strongly negative. 
E) Charges balance out and none of the atoms has any charge. 
A) The nitrogen is more slightly positive. 
B) The nitrogen is strongly negative. 
C) The hydrogens are more slightly positive. 
D) The hydrogens are strongly negative. 
E) Charges balance out and none of the atoms has any charge.

Question 17

The specific heat of water is 10 times greater than that of iron. You place a metal pot full of water on the stove to heat it up. You touch the metal handle of the pot when the water is still only lukewarm. Which of the following BEST describes what happens?

Accepted Answer

A) You find that the handle is cooler than the water in the pot. 
B) You burn your finger and pull your hand away from the very hot handle. 
C) You find that both the water and the handle are the same temperature. 
D) You determine that metal pots full of water produce acids and bases. 
A) You find that the handle is cooler than the water in the pot. 
B) You burn your finger and pull your hand away from the very hot handle. 
C) You find that both the water and the handle are the same temperature. 
D) You determine that metal pots full of water produce acids and bases.

Question 18

Acids have pH values below 7, while bases have pH values above 7. True or False?

Accepted Answer

A) True 
 B)False

Question 19

The water strider skates along the surface of water due to a property of liquids called ________.

Accepted Answer

The answer of The water strider skates along the surface...

Question 20

The formation of sodium chloride (NaCl)is the result of:

Accepted Answer

A) covalent bonding. 
B) chemical unreactivity. 
C) attraction between opposite charges. 
D) the lack of chemical attraction. 
A) covalent bonding. 
B) chemical unreactivity. 
C) attraction between opposite charges. 
D) the lack of chemical attraction.

Exam 2: Atoms, Molecules, and Life

What does HOH represent?

The fact that salt dissolves in water is BEST explained by the:

Most biological molecules are joined by:

The atomic number of an atom is defined as the:

Water molecules are cohesive because they:

Phosphorus has an atomic number of 15, so what is the distribution of its electrons?

What is the difference between covalent and ionic bonds?

Which of the following could potentially be a free radical?

If a substance measures 7 on the pH scale, that substance:

Which of the following is attracted to the hydrogen "end" of a water molecule, as depicted in this figure?

The human body must maintain a constant pH. In the blood, bicarbonate serves as a(n)________ to help maintain the necessary pH.

How do buffers work?

Which of the following pairs has the most similar chemical properties?

Which four elements make up approximately 96% of living matter?

Sulfur is an essential element in the human body, and studying its characteristics is important in understanding human physiology. Sulfur atoms have six electrons in their outer shell. Based on this information, which of the following is true?

An atom of nitrogen attracts electrons more strongly than an atom of hydrogen. Which of the following BEST describes ammonia (NH3)?

The specific heat of water is 10 times greater than that of iron. You place a metal pot full of water on the stove to heat it up. You touch the metal handle of the pot when the water is still only lukewarm. Which of the following BEST describes what happens?

Acids have pH values below 7, while bases have pH values above 7. True or False?

The water strider skates along the surface of water due to a property of liquids called ________.

The formation of sodium chloride (NaCl)is the result of:

An Introduction to Life on Earth

Biological Molecules

Cell Structure and Function

Cell Membrane Structure and Function

Energy Flow in the Life of a Cell

Capturing Solar Energy: Photosynthesis

Harvesting Energy: Glycolysis and Cellular Respiration

The Continuity of Life: Cellular Reproduction

Patterns of Inheritance

Dna: the Molecule of Heredity

Gene Expression and Regulation

Biotechnology

Principles of Evolution

How Populations Evolve

The Origin of Species

The History of Life

Systematics: Seeking Order Amidst Diversity

The Diversity of Prokaryotes and Viruses

The Diversity of Protists

The Diversity of Plants

The Diversity of Fungi

Animal Diversity I: Invertebrates

Animal Diversity Ii: Vertebrates

Animal Behavior

Population Growth and Regulation

Community Interactions

How Do Ecosystems Work

Earths Diverse Ecosystems

Conserving Earths Biodiversity

Homeostasis and the Organization of the Animal Body

Circulation

Respiration

Nutrition and Digestion

The Urinary System

Defenses Against Disease

Chemical Control of the Animal Body: the Endocrine System

The Nervous System

The Senses

Action and Support: the Muscles and Skeleton

Animal Reproduction

Animal Development

Plant Anatomy and Nutrient Transport

Plant Reproduction and Development

Plant Responses to the Environment

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