Question 1

C14 is a radioactive isotope, and it turns into _____________ when it decays.

Accepted Answer

nitrogen

Question 2

Which of these statements is false concerning covalent bonds?

Accepted Answer

A)  Atoms share electrons. 
B)  Molecules may possess many covalent bonds. 
C)  Water contains polar covalent bonds. 
D)  Covalent bonds may be "double bonds." 
E)  In polar covalent bonds, electrons are shared equally. 
A)  Atoms share electrons. 
B)  Molecules may possess many covalent bonds. 
C)  Water contains polar covalent bonds. 
D)  Covalent bonds may be "double bonds." 
E)  In polar covalent bonds, electrons are shared equally. E

Question 3

A molecule is

Accepted Answer

A)  a combination of two or more atoms. 
B)  a mixture of atoms. 
C)  electrically charged. 
D)  a carrier of one or more extra neutrons. 
E)  none of these. 
A)  a combination of two or more atoms. 
B)  a mixture of atoms. 
C)  electrically charged. 
D)  a carrier of one or more extra neutrons. 
E)  none of these. A

Question 4

The ability of a solution to resist changes in pH depends on its ______________.

Accepted Answer

The answer of The ability of a solution to resist...

Question 5

A salt will dissolve in water to form

Accepted Answer

A)  acids. 
B)  hydrogen bonds. 
C)  ions other than H+ and OH-. 
D)  bases. 
E)  buffers. 
A)  acids. 
B)  hydrogen bonds. 
C)  ions other than H+ and OH-. 
D)  bases. 
E)  buffers.

Question 6

MATCHING
Classification.The various energy levels in an atom of magnesium (   
) have different numbers of electrons.Use the numbers below to answer the following questions.
a.1
b.2
c.3
d.6
e.8
-number of electrons in the third energy level

Accepted Answer

The answer of MATCHING
Classification.The various energy levels in an atom...

Question 7

The atomic number refers to the

Accepted Answer

A)  mass of an atom. 
B)  number of protons in an atom. 
C)  number of both protons and neutrons in an atom. 
D)  number of neutrons in an atom. 
E)  number of electrons in an atom. 
A)  mass of an atom. 
B)  number of protons in an atom. 
C)  number of both protons and neutrons in an atom. 
D)  number of neutrons in an atom. 
E)  number of electrons in an atom.

Question 8

Radioactive isotopes have

Accepted Answer

A)  excess electrons. 
B)  excess protons. 
C)  excess neutrons. 
D)  insufficient neutrons. 
E)  insufficient protons. 
A)  excess electrons. 
B)  excess protons. 
C)  excess neutrons. 
D)  insufficient neutrons. 
E)  insufficient protons.

Question 9

In a chemical equation, the chemicals to the left of the arrow are

Accepted Answer

A)  products. 
B)  in greater abundance. 
C)  at higher energy levels. 
D)  reactants. 
E)  all of these. 
A)  products. 
B)  in greater abundance. 
C)  at higher energy levels. 
D)  reactants. 
E)  all of these.

Question 10

Toxic elements such as mercury are found in the human body because

Accepted Answer

A)  of contamination from the environment. 
B)  trace amounts of these elements have vital biological functions. 
C)  they are needed to kill bacteria. 
D)  they may be ingested with food but inactivated by cells. 
E)  in small amounts they are biologically inactive and tolerated by cells. 
A)  of contamination from the environment. 
B)  trace amounts of these elements have vital biological functions. 
C)  they are needed to kill bacteria. 
D)  they may be ingested with food but inactivated by cells. 
E)  in small amounts they are biologically inactive and tolerated by cells.

Question 11

Which statement is false?

Accepted Answer

A)  A molecule is made of at least two atoms. 
B)  Compounds are made of elements. 
C)  Two atoms of oxygen make a molecule of oxygen. 
D)  Proportions of elements in compounds vary according to their source in nature. 
E)  Elements are found in compounds and molecules. 
A)  A molecule is made of at least two atoms. 
B)  Compounds are made of elements. 
C)  Two atoms of oxygen make a molecule of oxygen. 
D)  Proportions of elements in compounds vary according to their source in nature. 
E)  Elements are found in compounds and molecules.

Question 12

An atom with more protons than electrons is called a(n) __________.

Accepted Answer

The answer of An atom with more protons than electrons...

Question 13

MATCHING
Classification.The various energy levels in an atom of magnesium (   
) have different numbers of electrons.Use the numbers below to answer the following questions.
a.1
b.2
c.3
d.6
e.8
-number of electrons in the first energy level

Accepted Answer

The answer of MATCHING
Classification.The various energy levels in an atom...

Question 14

Which of the following is NOT accurate concerning ionization?

Accepted Answer

A)  When one atom loses electrons, another must gain electrons. 
B)  When an atom loses an electron, it becomes negatively charged. 
C)  Ionic bonds form between ionized atoms. 
D)  In the compound NaCl, Na loses an electron to become positive. 
E)  In an ion, the number of protons and electrons is unequal. 
A)  When one atom loses electrons, another must gain electrons. 
B)  When an atom loses an electron, it becomes negatively charged. 
C)  Ionic bonds form between ionized atoms. 
D)  In the compound NaCl, Na loses an electron to become positive. 
E)  In an ion, the number of protons and electrons is unequal.

Question 15

Tracers are elements that

Accepted Answer

A)  are used in minute amounts in plants. 
B)  can be monitored through biochemical reactions. 
C)  must be inert. 
D)  have an unbalanced electrical charge. 
E)  must have a stable nucleus. 
A)  are used in minute amounts in plants. 
B)  can be monitored through biochemical reactions. 
C)  must be inert. 
D)  have an unbalanced electrical charge. 
E)  must have a stable nucleus.

Question 16

Blood pH is kept near a value of 7.3 - 7.5 because of

Accepted Answer

A)  salts. 
B)  buffers. 
C)  acids. 
D)  bases. 
E)  water. 
A)  salts. 
B)  buffers. 
C)  acids. 
D)  bases. 
E)  water.

Question 17

The subatomic particle(s) with a negative charge is(are)

Accepted Answer

A)  the neutron. 
B)  the proton. 
C)  the electron. 
D)  both the neutron and proton. 
E)  both the proton and electron. 
A)  the neutron. 
B)  the proton. 
C)  the electron. 
D)  both the neutron and proton. 
E)  both the proton and electron.

Question 18

Argon has 18 protons.How many electrons are in its third energy level?

Accepted Answer

A)  2 
B)  4 
C)  6 
D)  8 
E)  10 
A)  2 
B)  4 
C)  6 
D)  8 
E)  10

Question 19

Which is the smallest unit of an element that retains the properties of the element?

Accepted Answer

A)  atom 
B)  compound 
C)  ion 
D)  molecule 
E)  mixture 
A)  atom 
B)  compound 
C)  ion 
D)  molecule 
E)  mixture

Question 20

The most likely reason that glucose dissolves in water is that it is

Accepted Answer

A)  an ionic compound. 
B)  a polysaccharide. 
C)  polar and forms many hydrogen bonds with the water molecules. 
D)  a very unstable molecule. 
E)  highly nonpolar. 
A)  an ionic compound. 
B)  a polysaccharide. 
C)  polar and forms many hydrogen bonds with the water molecules. 
D)  a very unstable molecule. 
E)  highly nonpolar.

Exam 2: Lifes Chemical Basis

C14 is a radioactive isotope, and it turns into _____________ when it decays.

Which of these statements is false concerning covalent bonds?

A molecule is

The ability of a solution to resist changes in pH depends on its ______________.

A salt will dissolve in water to form

MATCHING Classification.The various energy levels in an atom of magnesium ( ) have different numbers of electrons.Use the numbers below to answer the following questions. a.1 b.2 c.3 d.6 e.8 -number of electrons in the third energy level

The atomic number refers to the

Radioactive isotopes have

In a chemical equation, the chemicals to the left of the arrow are

Toxic elements such as mercury are found in the human body because

Which statement is false?

An atom with more protons than electrons is called a(n) __________.

MATCHING Classification.The various energy levels in an atom of magnesium ( ) have different numbers of electrons.Use the numbers below to answer the following questions. a.1 b.2 c.3 d.6 e.8 -number of electrons in the first energy level

Which of the following is NOT accurate concerning ionization?

Tracers are elements that

Blood pH is kept near a value of 7.3 - 7.5 because of

The subatomic particle(s) with a negative charge is(are)

Argon has 18 protons.How many electrons are in its third energy level?

Which is the smallest unit of an element that retains the properties of the element?

The most likely reason that glucose dissolves in water is that it is

Invitation to Biology

Molecules of Life

Cell Structure and Function

Ground Rules of Metabolism

Where It Startsphotosynthesis

How Cells Release Chemical Energy

Dna Structure and Function

From Dna to Protein

Gene Control

How Cells Reproduce

Meiosis and Sexual Reproduction

Observing Patterns in Inherited Traits

Chromosomes and Human Inheritance

Studying and Manipulating Genomes

Evidence of Evolution

Processes of Evolution

Organizing Information About Species

Lifes Origin and Early Evolution

Viruses and Prokaryotes

Protiststhe Simplest Eukaryotes

The Land Plants

Fungi

Animal Evolutionthe Invertebrates

Animal Evolutionthe Chordates

Animal Evolutionhuman Evolution

Plant Tissues

Plant Nutrition and Transport

Life Cycles of Flowering Plants

Communication Strategies in Plants

Animal Tissues and Organ Systems

Neural Control

Sensory Perception

Endocrine Control

Structural Support and Movement

Circulation

Immunity

Respiration

Digestion and Nutrition

Maintaining the Internal Environment

Animal Reproductive Systems

Animal Development

Animal Behavior

Population Ecology

Community Ecology

Ecosystems

The Biosphere

Human Impacts on the Biosphere

Filters

C¹⁴ is a radioactive isotope, and it turns into _____________ when it decays.