BMSC 200 - Module 2 Exam Questions
with Complete Answers
Ionic Interaction - ANSWER-An interaction between electrically charged groups;
attractive between groups of opposite charge, repulsive between groups of the same
charge
hydrogen bond - ANSWER-A weak electrostatic attraction between one
electronegative atom (such as oxygen or nitrogen) and a hydrogen atom covalently
linked (donor) to a second electronegative atom that has a free electron pair
(acceptor)
Intramolecular - ANSWER-limited within the structure of a single molecule
Intermolecular - ANSWER-limited within the structures of different molecules. For
example, forces of attraction or repulsion between neighboring, different entities
What is the most abundant molecule in living systems? - ANSWER-Water is the
most abundant in living systems. About 70% of the cell.
What roles does water has? - ANSWER-Has active and passive roles in biological
systems
Passive role of water - ANSWER-The structures of biomolecules are formed in
response to their interaction with water
Active role of water - ANSWER-Water is a participant in any biochemical reactions
Electronegativities of water - ANSWER-Oxygen and hydrogen differ in their
electronegativities. Oxygen is more electronegative and as a result, water has a
permanent dipole/polarity.
Dipole of water charges - ANSWER-Water has a permanent dipole with O having a
partial negative charge and H having a partial positive charge.
Why is the polarity of water essential? - ANSWER-It is essential in its ability to
interact with other water molecules and other biomolecules
How does the dipole of water dictate water's abilities? - ANSWER-The dipole
dictates water's ability to:
1) form electrostatic interactions
2) form hydrogen bonds
, What is the lenght of a hydrogen bond? - ANSWER-It is double that of a covalent
bond
What bonds are the donors and acceptors linked through? - ANSWER-The donor is
linked through a covalent bond and the acceptor is linked through a hydrogen bond
diagram for hydrogen bond - ANSWER-D-H------A
What atoms are the most common hydrogen bond donors and acceptors? -
ANSWER-Oxygen and nitrogen
What are hydrogen bonds a form of? - ANSWER-They are a form of non-covalent
interaction
Strenght of hydrogen bond - ANSWER-The strenght of the hydrogen are individually
weak (about 5% the strenght of a covalent bond) but they depend on its geometry
Which is the stronger hydrogen bond?
H hydrogen bonded to O at 90 degrees
or
H hydrogen bonded to ) at 45 degrees - ANSWER-H hydrogen bonded to O at 90
degrees
How many bonds can water donate or accept? - ANSWER-Each water molecule can
donate two hydrogen bonds and accept two
hydrogen bonds
Why does water have a great inter cohesion? - ANSWER-The sum of all the
hydrogen bonds between water molecules confers great
internal cohesion on liquid water.
Which parts of the hydrogen bonds act as acceptors and donors? - ANSWER-
hydrogens act as donors and electron pairs act as acceptors
Why does water have a high melting point, high boiling point, high heat
of vaporization and specific heat capacity? - ANSWER-The large number of
hydrogen bonds in water that give water a great internal cohesion contributes to its
high melting and boiling point, heat of vaporization and specific heat capacity.
Heat of Vaporization - ANSWER-The amount of heat requires to vaporize a liquid at
its boiling temp
Specific Heat Capacity - ANSWER-The amount of heat required to raise the
temperature of a substance one degree.
with Complete Answers
Ionic Interaction - ANSWER-An interaction between electrically charged groups;
attractive between groups of opposite charge, repulsive between groups of the same
charge
hydrogen bond - ANSWER-A weak electrostatic attraction between one
electronegative atom (such as oxygen or nitrogen) and a hydrogen atom covalently
linked (donor) to a second electronegative atom that has a free electron pair
(acceptor)
Intramolecular - ANSWER-limited within the structure of a single molecule
Intermolecular - ANSWER-limited within the structures of different molecules. For
example, forces of attraction or repulsion between neighboring, different entities
What is the most abundant molecule in living systems? - ANSWER-Water is the
most abundant in living systems. About 70% of the cell.
What roles does water has? - ANSWER-Has active and passive roles in biological
systems
Passive role of water - ANSWER-The structures of biomolecules are formed in
response to their interaction with water
Active role of water - ANSWER-Water is a participant in any biochemical reactions
Electronegativities of water - ANSWER-Oxygen and hydrogen differ in their
electronegativities. Oxygen is more electronegative and as a result, water has a
permanent dipole/polarity.
Dipole of water charges - ANSWER-Water has a permanent dipole with O having a
partial negative charge and H having a partial positive charge.
Why is the polarity of water essential? - ANSWER-It is essential in its ability to
interact with other water molecules and other biomolecules
How does the dipole of water dictate water's abilities? - ANSWER-The dipole
dictates water's ability to:
1) form electrostatic interactions
2) form hydrogen bonds
, What is the lenght of a hydrogen bond? - ANSWER-It is double that of a covalent
bond
What bonds are the donors and acceptors linked through? - ANSWER-The donor is
linked through a covalent bond and the acceptor is linked through a hydrogen bond
diagram for hydrogen bond - ANSWER-D-H------A
What atoms are the most common hydrogen bond donors and acceptors? -
ANSWER-Oxygen and nitrogen
What are hydrogen bonds a form of? - ANSWER-They are a form of non-covalent
interaction
Strenght of hydrogen bond - ANSWER-The strenght of the hydrogen are individually
weak (about 5% the strenght of a covalent bond) but they depend on its geometry
Which is the stronger hydrogen bond?
H hydrogen bonded to O at 90 degrees
or
H hydrogen bonded to ) at 45 degrees - ANSWER-H hydrogen bonded to O at 90
degrees
How many bonds can water donate or accept? - ANSWER-Each water molecule can
donate two hydrogen bonds and accept two
hydrogen bonds
Why does water have a great inter cohesion? - ANSWER-The sum of all the
hydrogen bonds between water molecules confers great
internal cohesion on liquid water.
Which parts of the hydrogen bonds act as acceptors and donors? - ANSWER-
hydrogens act as donors and electron pairs act as acceptors
Why does water have a high melting point, high boiling point, high heat
of vaporization and specific heat capacity? - ANSWER-The large number of
hydrogen bonds in water that give water a great internal cohesion contributes to its
high melting and boiling point, heat of vaporization and specific heat capacity.
Heat of Vaporization - ANSWER-The amount of heat requires to vaporize a liquid at
its boiling temp
Specific Heat Capacity - ANSWER-The amount of heat required to raise the
temperature of a substance one degree.
