+
Related Flashcards
Cards In This Set
| Front | Back |
|
1) About
25 of the 92 natural elements are known to be essential to life. Which four of
these 25 elements make up approximately 96% of living matter?
A) carbon,
sodium, chlorine, nitrogen
B)
carbon, sulfur, phosphorus, hydrogen
C)
oxygen, hydrogen, calcium, sodium
D)
carbon, hydrogen, nitrogen, oxygen
E)
carbon, oxygen, sulfur, calcium
|
D
|
|
2) Trace
elements are those required by an organism in only minute quantities. Which of
the following is a trace element that is required by humans and other
vertebrates?
A)
nitrogen
B)
calcium
C) iodine
D) sodium
E)
phosphorus
|
C
|
|
3) Three
or four of the following statements are true and correct. Which one, if any, is
false? If all the statements are true, choose answer E.
A)
Carbon, hydrogen, oxygen, and nitrogen make up approximately 96% of living
matter.
B) The
trace element iodine is required only in very small quantities by vertebrates.
C)
Virtually all organisms require the same elements in the same quantities.
D) Iron
is an example of an element needed by all organisms.
E) All of
the other statements are true and correct.
|
C
|
|
4) Which
of the following statements is false?
A) Atoms
of the various elements differ in their number of subatomic particles.
B) All
atoms of a particular element have the same number of protons in their nuclei.
C) The
neutrons and protons present in the nucleus of an atom are almost identical in
mass; each has a mass of about 1 dalton.
D) An
atom is the smallest unit of an element that still retains the properties of
the element.
E)
Protons and electrons are electrically charged particles. Protons have one unit
of negative charge, and electrons have one unit of positive charge.
|
E
|
|
5) Each
element is unique and different from other elements because of the number of
protons in the nuclei of its atoms. Which of the following indicates the number
of protons in an atom's nucleus?
A) atomic
mass
B) atomic
weight
C) atomic
number
D) mass
weight
E) mass
number
|
C
|
|
6) The
mass number of an element can be easily approximated by adding together the
number of __________ in an atom of that element.
A)
protons and neutrons
B) energy
levels
C)
protons and electrons
D)
neutrons and electrons
E)
isotopes
|
A
|
|
7) What
is the approximate atomic mass of an atom with 16 neutrons, 15 protons, and 15
electrons?
A) 15 daltons
B) 16
daltons
C) 30
daltons
D) 31
daltons
E) 46
daltons
|
D
|
|
8) Oxygen
has an atomic number of 8 and a mass number of 16. Thus, the atomic mass of an
oxygen atom is
A)
exactly 8 grams.
B)
exactly 8 daltons.
C)
approximately 16 grams.
D)
approximately 16 daltons.
E) 24 amu
(atomic mass units).
|
D
|
|
9) The
nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the
following is a correct statement concerning nitrogen?
A) The
nitrogen atom has a mass number of approximately 7 daltons and an atomic mass
of 14.
B) The
nitrogen atom has a mass number of approximately 14 daltons and an atomic mass
of 7.
C) The
nitrogen atom has a mass number of 14 and an atomic mass of 7 grams.
D) The
nitrogen atom has a mass number of 7 grams and an atomic number of 14.
E) The
nitrogen atom has a mass number of 14 and an atomic mass of approximately 14
daltons.
|
E
|
|
10)
Calcium has an atomic number of 20 and an atomic mass of 40. Therefore, a
calcium atom must have
A) 20
protons.
B) 40
electrons.
C) 40
neutrons.
D) A and
B only
E) A, B,
and C
|
A
|
|
11) An
atom with an atomic number of 9 and a mass number of 19 would have an atomic
mass of approximately
A) 9
daltons.
B) 9
grams.
C) 10
daltons.
D) 20
grams.
E) 19
daltons.
|
E
|
|
12)
Different atomic forms of an element contain the same number of protons but a
different number of neutrons. What are these different atomic forms called?
A) ions
B)
isotopes
C)
neutronic atoms
D) isomers
E)
radioactive atoms
|
B
|
|
13) How
do isotopes of the same element differ from each other?
A) number
of protons
B) number
of electrons
C) number
of neutrons
D)
valence electron distribution
E) amount
of radioactivity
|
C
|
|
One
difference between carbon-12 ( C) and carbon-14 ( C) is that carbon-14 has
A) two
more protons than carbon-12.
B) two
more electrons than carbon-12.
C) two
more neutrons than carbon-12.
D) A and
C only
E) B and
C only
|
C
|
|
H is a radioactive isotope of hydrogen. One difference between hydrogen-1
( H) and hydrogen-3 ( H) is that hydrogen-3 has
A) one
more neutron and one more proton than hydrogen-1.
B) one
more proton and one more electron than hydrogen-1.
C) one
more electron and one more neutron than hydrogen-1.
D) two
more neutrons than hydrogen-1.
E) two
more protons than hydrogen-1.
|
D
|
