MCB 2000 (UConn) Exam 1 Practice
Questions All Solved Correct 2025-
2026 Updated.
covalent vs. noncovalent interactions- how are they different? - Answer
Electronegativity - Answer
Polarity - Answer Molecules having uneven distribution of charges
polar: unequal sharing, involved an electronegative atom
nonpolar: equal sharing
what is polarity important? - Answer -explains why molecules are hydrophilic and
hydrophobic
-leads to noncovalent interactions
hydrophobic effect - Answer -Inability of water to dissolve nonpolar molecules results in this
important organizing principle.
-nonpolar molecules cannot form H bonds with water
-hydrophobic molecules cluster together in aqueous solutions
-powered by the increase in the entropy of water that results when hydrophobic molecules
come together
*powerful organizing force
what makes hydrophobic interactions favorable? - Answer entropy (S)
-drives the interaction between nonpolar molecules
-hydrophobic interactions allow for an increase in entropy of water
entropy (S) - Answer a measure of the disorder of a system
-high: disordered state
-low: ordered state
, types of covalent interactions - Answer nonpolar, polar
-stable
-do not break and form spontaneously
noncovalent interactions - Answer -Hydrogen bonds
-Electrostatic, ionic interactions
-Van der Waals forces
-Hydrophobic interactions
hydrogen bonding - Answer
Electrostatic (ionic) interactions - Answer -attraction/repulsion
-occurs between atoms with a complete negative charge or a complete positive charge
-strength determined by distance and solvent
*importance: protein-protein interactions, DNA-protein interactions, catalytic mechanisms
dielectric constant - Answer high: greater ability to dissolve salts
* water has a high dielectric constant
van der Waals forces - Answer -basis: transient asymmetry in the electron distribution of one
molecule will induce complementary asymmetry in a nearby molecule
-result: charge fluctuations transiently produces + and - poles even in nonpolar molecule
-distance matters: present with "snug fit" between atoms
-weakest of noncovalent interactions
noncovalent interactions - Answer -Hydrogen bonds
-Electrostatic, ionic interactions
-Van der Waals forces
-Hydrophobic interactions
what chemical properties of water contribute to its uniqueness? - Answer H-bonding,
polarity, and reversible ionization.
Questions All Solved Correct 2025-
2026 Updated.
covalent vs. noncovalent interactions- how are they different? - Answer
Electronegativity - Answer
Polarity - Answer Molecules having uneven distribution of charges
polar: unequal sharing, involved an electronegative atom
nonpolar: equal sharing
what is polarity important? - Answer -explains why molecules are hydrophilic and
hydrophobic
-leads to noncovalent interactions
hydrophobic effect - Answer -Inability of water to dissolve nonpolar molecules results in this
important organizing principle.
-nonpolar molecules cannot form H bonds with water
-hydrophobic molecules cluster together in aqueous solutions
-powered by the increase in the entropy of water that results when hydrophobic molecules
come together
*powerful organizing force
what makes hydrophobic interactions favorable? - Answer entropy (S)
-drives the interaction between nonpolar molecules
-hydrophobic interactions allow for an increase in entropy of water
entropy (S) - Answer a measure of the disorder of a system
-high: disordered state
-low: ordered state
, types of covalent interactions - Answer nonpolar, polar
-stable
-do not break and form spontaneously
noncovalent interactions - Answer -Hydrogen bonds
-Electrostatic, ionic interactions
-Van der Waals forces
-Hydrophobic interactions
hydrogen bonding - Answer
Electrostatic (ionic) interactions - Answer -attraction/repulsion
-occurs between atoms with a complete negative charge or a complete positive charge
-strength determined by distance and solvent
*importance: protein-protein interactions, DNA-protein interactions, catalytic mechanisms
dielectric constant - Answer high: greater ability to dissolve salts
* water has a high dielectric constant
van der Waals forces - Answer -basis: transient asymmetry in the electron distribution of one
molecule will induce complementary asymmetry in a nearby molecule
-result: charge fluctuations transiently produces + and - poles even in nonpolar molecule
-distance matters: present with "snug fit" between atoms
-weakest of noncovalent interactions
noncovalent interactions - Answer -Hydrogen bonds
-Electrostatic, ionic interactions
-Van der Waals forces
-Hydrophobic interactions
what chemical properties of water contribute to its uniqueness? - Answer H-bonding,
polarity, and reversible ionization.
