Lecture 1

Question 1

For the following macromolecule, state the terms for it’s Monomer, polymer, and the name of the bonds between it’s monomers.

Carbohydrates

Answer 1

Monomer: Monosaccharides

Polymer: Disaccharide, or Polysaccharide

Name of bonds: Glycosidic

Question 2

For the following macromolecule, state the terms for it’s Monomer, polymer, and the name of the bonds between it’s monomers.

Lipids

Answer 2

Monomer: Fatty acids + glycerol or sphingosine derivatives

Polymer: Triacyglycerol or sphingolipids

Name of bonds: ester

Question 3

For the following macromolecule, state the terms for it’s Monomer, polymer, and the name of the bonds between it’s monomers.

Proteins

Answer 3

Monomer: AA’s

Polymer: Polypeptide

Name of bonds: Peptide

Question 4

For the following macromolecule, state the terms for it’s Monomer, polymer, and the name of the bonds between it’s monomers.

Nucleic acids

Answer 4

Monomer: Nucleotides

Polymer: Oligonucleotides, or Polynucleotides

Name of bonds: Phosphodiester

Question 5

Name 2 types of electrostatic interactions

Answer 5

Ionic Bonds (NaCl)

Salt Bridges (interaction between 2 AA’s in a protein)

Question 6

Define the term Dipole and state the 2 types of dipoles that may occur. (include the specific terms for these)

Answer 6

Dipole: having a partial charge

Permanent dipoles are: polar

Induced dipoles are: polarizable

Question 7

True or False: in the gas phase, only some compounds can manage hydrogen bonding. explain.

Answer 7

False

there are no H bonds formed between gaseous compounds (atoms are flying around too quickly to establish this type of bond)????

Question 8

In general, Van der Waal interactions distances are going to be ____ compared to the distances of hydrogen bond interactions.

Answer 8

Longer

Question 9

For the following type of bond explain the interaction that is occurring, the bond distance, and bond energies (not explicit values, just in relation to one another)

Covalent Bonds

Answer 9

Interaction: share an electron pair

Bond distance: shortest (1A)

Bond energy: Strong (355 kJ/mol)

Question 10

For the following type of bond explain the interaction that is occurring, the bond distance, and bond energies (not explicit values, just in relation to one another)

Charge and/or dipole interactions

Answer 10

Interaction: Charge attraction

Bond distance: moderate (3A)

Bond energy: moderate (5.86 kJ/mol)

Question 11

For the following type of bond explain the interaction that is occurring, the bond distance, and bond energies (not explicit values, just in relation to one another)

Van der Waals interactions

Answer 11

Interaction: Charge attraction

Bond distance: moderate (3-4 A ; varies by atom size)

Bond energy: weakest (2-4 kJ/mol)

Question 12

For the following type of bond explain the interaction that is occurring, the bond distance, and bond energies (not explicit values, just in relation to one another)

Hydrogen Bonds

Answer 12

Interaction: Share a hydrogen atom/proton

Bond distance: moderate (2.6-3.7 A ; between donor and acceptor)

Bond energy: moderate (4-20 kJ/mol)

Question 13

compare the H bonding that occurs or does not occur in the 3 forms of water.

Answer 13

Solid: optimal H-bonding

Liquid: suboptimal H-bonding

Gas: no H-bonding

Question 14

True or False: water as a solid (ice) is more dense than water as a liquid. Explain

Answer 14

False

Water as a solid is less dense than it is as a liquid because it’s H bond distances are longer in it’s solid form, compared to water in it’s liquid form

Question 15

Compare the terms Cohesion and Adhesion and provide water-based examples

Answer 15

Cohesion: attraction to self
ex. water molecules are attracted to each other

Adhesion: attraction to other
ex. water and other polar substances attract each other

Question 16

How does cohesion make the surface of water strong?

Answer 16

cohesion creates surface tension

Question 17

What 2 forces work together to create capillary action?

Answer 17

cohesion and adhesion

Question 18

Compare Charged/Polar molecules and Nonpolar molecules in terms of how they interact with water

Answer 18

Charged/Polar molecules are hydrophilic and dissolve in water

Nonpolar molecules are hydrophobic and separate

Question 19

Define the term Amphipathic

Answer 19

amphipathic molecules have both hydrophilic and hydrophobic parts

ex. the phospholipid bilayer and cytoplasm portions of a cell

Question 20

Explain what must be occurring between 2 chemicals during a chemical reaction (2 options)

Answer 20

chemical reactions can only occur if there are chemical bonds being created or destroyed

Question 21

Most chemical reactions are _____. Explain how this can be true, yet many reactions seem to find a stable product.

Answer 21

reversible (dynamic)

reactions usually FAVOR a reactant formation or a product formation (especially when kept at a constant temperature)

Question 22

State the term that embodies the following statement: When a chemical reaction as reached a point where there is no NET formation or destruction.

Answer 22

Equilibrium

Question 23

Name the following equation and it’s use

E= k (q1q2/Dr)

Answer 23

Energy of interaction equation

used to derive the energy required to separate 2 ions in a biological environment

(D = dielectric constant of the solvent )
ex. methanol has a lower dielectric constant than water so the energy of interaction is higher in methanol

Question 24

Name the following equation and it’s use

E= k (q1q2/r^2)

Answer 24

Coulomb’s Law

used to derive the energy required to separate 2 ions in a VACUUM

(this does not have a dielectric constant bc it is not occurring in a a biological system)