BS 161 FINAL EXAM NEWEST EXAM
COMPLETE 280 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
ALREADY GRADED A+
Where do lipids, a class of organic compounds, fit on the
hierarchy of biological organization? - ANSWER >>>>DNA
What are characteristics of an ionic bond? - ANSWER
>>>>An electron is completely pulled from one atom to
another. The electronegativity difference is always high
between atoms of this bond type.
What are characteristics of a covalent bond? - ANSWER
>>>>Atoms of this bond might have equal electronegativities.
This bond may also be polar or nonpolar.
What are the 4 most common elements in living organisms? -
ANSWER >>>>Carbon, Oxygen, Hydrogen and Nitrogen
What elements are present in trace amounts only? -
ANSWER >>>>Iodine and Zinc
What elements are found in greater than trace amounts? -
ANSWER >>>>Sodium, Chloride, Calcium, phosphorus,
potassium, sulfur, magnesium and iron
The atomic number of carbon-13 is ____ - ANSWER >>>>6
The atomic mass of carbon-13 is ______ - ANSWER >>>>13
,C-12, C-13, and C-14 have the same number of protons but
different numbers of neutrons so they are ______. - ANSWER
>>>>Isotopes
Atoms have gained or lost electrons and are no longer
electrically neutral are called _____. - ANSWER >>>>Ions
Describe a single covalent bond. - ANSWER >>>>Holds a
molecule of hydrogen together, involves 2 atoms sharing 2
electrons and two chlorine atoms are held together by this
bond.
Describe an Ionic bond. - ANSWER >>>>Formed by an
attraction between atoms with opposite charges, bond that
hold NaCl together, Involves a transfer of one or more
electrons from one atom to another, Leads to the formation of
a crystal lattice rather than distinct molecules and Weakest
type of bond shown.
Describe a double covalent bond. - ANSWER >>>>hold a
molecule of oxygen together, Involves 2 atoms sharing 4
electrons, strongest type of bond shown and carbon dioxide is
held together by this type of bond.
T/F
A water molecule is held together by 2 single polar covalent
bond - ANSWER >>>>TRUE
T/F
Because oxygen has a greater electronegativity than
hydrogen, water molecules are polar w/ 2 partial negative
,charges near the oxygen atom and one partial positive charge
near each hydrogen atom. - ANSWER >>>>TRUE
T/F
Atoms differ in their affinity for neutrons, a property called
electronegativity. - ANSWER >>>>FALSE
T/F
In general, electronegativity increases from left to right across
each row of the periodic table and also increases down each
column. - ANSWER >>>>FALSE
T/F
In a nonpolar covalent bond there is an equal sharing of
electrons between two atoms while polar covalent bonds
involve an unequal sharing of electrons. - ANSWER
>>>>TRUE
T/F
A single molecule of Oxygen is held together by 2 double non
polar covalent bonds. - ANSWER >>>>FALSE
T/F
A covalent bond is formed when 2 atoms share one or more
pairs of electrons - ANSWER >>>>TRUE
T/F
Polar molecules are electrically neutral but the distribution of
charge within the molecule is not uniform. - ANSWER
>>>>TRUE
T/F
, Although C and H differ slightly in electronegativity, this small
difference is negligible and C-H bonds are considered polar. -
ANSWER >>>>FALSE
T/F
Of the 4 most common elements found in living organisms,
nitrogen has the highest electronegativity and therefore, the
greatest affinity for electrons. - ANSWER >>>>FALSE
T/F
A slightly positive hydrogen atom on one water molecule can
attract the slightly negative oxygen atom on a different water
molecule, leading to the formation of a hydrogen bond. -
ANSWER >>>>TRUE
What are properties of water? - ANSWER >>>>A wide variety
of substances can move freely and interact within cells, the
temp. of living organisms is relatively stable, evaporation of
water is used to cool body surface, lakes freeze from top
down, allowing fish and other life to survive below the surface
and non polar molecules tend to aggregate or organize in
ways that minimize their contact w water.
As the pH scale increases the concentration becomes______.
- ANSWER >>>>Greater
pH's H+ concentration increases by ___. - ANSWER >>>>10
When given electronegativity subtracting the difference
between the two molecules will provide you with what
information? - ANSWER >>>>If the atom is polar or nonpolar
COMPLETE 280 QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
ALREADY GRADED A+
Where do lipids, a class of organic compounds, fit on the
hierarchy of biological organization? - ANSWER >>>>DNA
What are characteristics of an ionic bond? - ANSWER
>>>>An electron is completely pulled from one atom to
another. The electronegativity difference is always high
between atoms of this bond type.
What are characteristics of a covalent bond? - ANSWER
>>>>Atoms of this bond might have equal electronegativities.
This bond may also be polar or nonpolar.
What are the 4 most common elements in living organisms? -
ANSWER >>>>Carbon, Oxygen, Hydrogen and Nitrogen
What elements are present in trace amounts only? -
ANSWER >>>>Iodine and Zinc
What elements are found in greater than trace amounts? -
ANSWER >>>>Sodium, Chloride, Calcium, phosphorus,
potassium, sulfur, magnesium and iron
The atomic number of carbon-13 is ____ - ANSWER >>>>6
The atomic mass of carbon-13 is ______ - ANSWER >>>>13
,C-12, C-13, and C-14 have the same number of protons but
different numbers of neutrons so they are ______. - ANSWER
>>>>Isotopes
Atoms have gained or lost electrons and are no longer
electrically neutral are called _____. - ANSWER >>>>Ions
Describe a single covalent bond. - ANSWER >>>>Holds a
molecule of hydrogen together, involves 2 atoms sharing 2
electrons and two chlorine atoms are held together by this
bond.
Describe an Ionic bond. - ANSWER >>>>Formed by an
attraction between atoms with opposite charges, bond that
hold NaCl together, Involves a transfer of one or more
electrons from one atom to another, Leads to the formation of
a crystal lattice rather than distinct molecules and Weakest
type of bond shown.
Describe a double covalent bond. - ANSWER >>>>hold a
molecule of oxygen together, Involves 2 atoms sharing 4
electrons, strongest type of bond shown and carbon dioxide is
held together by this type of bond.
T/F
A water molecule is held together by 2 single polar covalent
bond - ANSWER >>>>TRUE
T/F
Because oxygen has a greater electronegativity than
hydrogen, water molecules are polar w/ 2 partial negative
,charges near the oxygen atom and one partial positive charge
near each hydrogen atom. - ANSWER >>>>TRUE
T/F
Atoms differ in their affinity for neutrons, a property called
electronegativity. - ANSWER >>>>FALSE
T/F
In general, electronegativity increases from left to right across
each row of the periodic table and also increases down each
column. - ANSWER >>>>FALSE
T/F
In a nonpolar covalent bond there is an equal sharing of
electrons between two atoms while polar covalent bonds
involve an unequal sharing of electrons. - ANSWER
>>>>TRUE
T/F
A single molecule of Oxygen is held together by 2 double non
polar covalent bonds. - ANSWER >>>>FALSE
T/F
A covalent bond is formed when 2 atoms share one or more
pairs of electrons - ANSWER >>>>TRUE
T/F
Polar molecules are electrically neutral but the distribution of
charge within the molecule is not uniform. - ANSWER
>>>>TRUE
T/F
, Although C and H differ slightly in electronegativity, this small
difference is negligible and C-H bonds are considered polar. -
ANSWER >>>>FALSE
T/F
Of the 4 most common elements found in living organisms,
nitrogen has the highest electronegativity and therefore, the
greatest affinity for electrons. - ANSWER >>>>FALSE
T/F
A slightly positive hydrogen atom on one water molecule can
attract the slightly negative oxygen atom on a different water
molecule, leading to the formation of a hydrogen bond. -
ANSWER >>>>TRUE
What are properties of water? - ANSWER >>>>A wide variety
of substances can move freely and interact within cells, the
temp. of living organisms is relatively stable, evaporation of
water is used to cool body surface, lakes freeze from top
down, allowing fish and other life to survive below the surface
and non polar molecules tend to aggregate or organize in
ways that minimize their contact w water.
As the pH scale increases the concentration becomes______.
- ANSWER >>>>Greater
pH's H+ concentration increases by ___. - ANSWER >>>>10
When given electronegativity subtracting the difference
between the two molecules will provide you with what
information? - ANSWER >>>>If the atom is polar or nonpolar
