Chapter 2

Question 1

What are atoms composed of?

Answer 1

1. ) Nucleus: contains neutrons and protons

2. ) Electrons orbiting in the cloud

Question 2

Atoms Mass#=?

Answer 2

protons + neutrons

Question 3

Atoms atomic #=?

Answer 3

protons

Question 4

What are the most abundant biological elements?

Answer 4

Carbon, oxygen, hydrogen, nitrogen

Question 5

Out of the most abundant biological elements what are their valence’s?

Answer 5

C: 4
O: 2
H: 1
N: 3

Question 6

Valence:

Answer 6

the amount of electrons that are available to pair to complete an atoms octet.

Question 7

Ionic vs. Covalent bond?

Answer 7

Ionic: one atom steals an electron from anther causing it to take a negative charge and the other atom to take a positive charge thus drawing the two together
Covalent: atoms share electrons and those electrons orbit the joint atoms

Question 8

When do ionic bonds typically occur?

Answer 8

When there is a large variance in electronegativity.

Question 9

When do covalent bonds typically occur?

Answer 9

When there is little to no variance in electronegativity between atoms.

Question 10

Predictability of the electronegativity of four most common biologically abundant elements:

Answer 10

O»N>C=H

Question 11

Bond dissociation energy?

Answer 11

energy needed to break a bond

Question 12

potential energy?

Answer 12

the energy released after breaking a bond that is then transformed to a variety of of forms of energy’s.

Question 13

Describe the bond dissociation and potential energy as a covalent bond becomes more polar?

Answer 13

bond dissociation energy increases and potential energy decreases.

Question 14

Describe the bond dissociation and potential energy as a covalent bond becomes more nonpolar?

Answer 14

bond dissociation energy decreases and potential energy increases.

Question 15

Describe Hydrogen bonds?

Answer 15

• when ever a hydrogen bonds with anther atom typically an oxygen atom. ( this is due to the partial negative charge)
• The differing partial charges will attract other atoms to form weak hydrogen bonds.

Question 16

What are five interesting properties of water that result from it’s hydrogen bonds?

Answer 16

1. ) outstanding solvent for charged/polar particles
2. ) nonpolar molecules are unable to make hydrogen bonds, therefore when exposed to water they remain separate.
3. ) Water has a high surface tension ( meniscus in a graduated cylinder)
4. ) water is more dense as a liquid than a solid
5. ) hydrogen bonds are great at absorbing heat and give H2O a high heat of vaporization

Question 17

PH scale:

Answer 17

The scale showing the amount of dissolved protons in a solution

Question 18

How to acids and bases differ in proton concentration?

Answer 18

Acids= higher proton concentration
Bases= lower proton concentration

Question 19

What is the equation to determine PH?

Answer 19

pH=-log{H+}

Question 20

What is the equation to determine the amount of protons in a solution?

Answer 20

{H+}= antilog(-ph)

Question 21

What does Ph serve to do?

Answer 21

It is important in cells and living systems, as it is required to be balanced to perform biomechanical processes.

Question 22

What is a buffer?

What is the example mentioned in lecture?

Answer 22

When a buffer is dissolved in solution it serves to reset the imbalance seen.

Question 23

What is the example of a buffer mentioned in lecture?

Answer 23

CO2 + H2O –>

Question 24

Potential energy?

Answer 24

Stored energy (chemical)

Question 25

Kinetic energy?

Answer 25

energy of motion (thermal energy)

Question 26

What is Gibbs Free energy (g)?

Answer 26

Free energy change associated with a chemical reaction

Question 27

What is the equation to determine the change in Gibbs free energy? Derive each unit of the equation

Answer 27

``` DeltaG= DeltaH - T * DeltaS DeltaG = change in Gibbs Free energy DeltaH = change in enthalpy T = temperature DeltaS = change in entrophy or randomness ```

Question 28

What does it mean if DeltaG < 0 ? | What does it mean if DeltaG > 0 ?

Answer 28

1. ) the products are at a lower energy state than the reactants, therefore it is exergonic 2. ) The products are at a higher energy state than the reactants, therefore is is endergonic

Question 29

How can we make an educated guess on the outcome of Delta G?

Answer 29

1.) Determine which side ( products or reactants) have more nonpolar bonds, the one with more nonpolar covalent bonds has a higher potential energy. 2.) the side with more nonpolar covalent bonds has a high enthalpy and the side with less a low enthalpy. subtract the products from the reactants and note weather the value is less than or greater than zero. 3.) Next we can look at DeltaS or change in entrophy. To do this look for which side has larger and more structured molecules. The S will be higher on the side with smaller and less complex molecules, finally subtract the products from the reactants and not if the delta S is less than or greater than zero. 4.) Temperature will always be positive because we are working in units of kelvin, therefor u plug in the values from earlier and see if delta G is less than or greater than zero.

Question 30

What molecules were present and abundant on the pre-biotic earth?

Answer 30

CO2 ( most abundant source of carbon) H2O, N2, NH3, CH4, and H2

Question 31

What was the problem with CO2?

Answer 31

The carbon in CO2 isn't very reactive, because of its polar covalent bonds that have a high dissociation and low potential energy.

Question 32

What are REDOX reactions?

Answer 32

The process of a carbon become more complex so it becomes more reactive and is able to create more complex molecules.

Question 33

What does reduced mean?

Answer 33

Gains electrons

Question 34

What was Stanley Miller known for?

Answer 34

A simulation of the early atmosphere to show carbon in reduced forms is very possible on the probiotic earth.

Question 35

Where did energy in the atmosphere come from?

Answer 35

Sun

Question 36

What are Free Radius atoms?

Answer 36

atoms or molecules that contain highly reactive unpaired molecules

Question 37

what is the probiotic soup model?

Answer 37

- Atmospheric gases dissolve in the water and light energy initiates carbon reduction - Then hydrogen cyanide/formaldehyde can form. - These combined with heat can react with heat to form more complex carbon based compounds that were necessary for life on earth.

Question 38

What is the surface metabolism model?

Answer 38

- The focus is on the geologically dynamic vents located in the bottom of the ocean - The vents are hot and high in pressure, and their insides are very rigid and full of crevice's. - molecules gather in these crevice's and obv. increase in concentration. - Increased concentration combined with the environmental factors creates carbon reduction which allows for it form more complex compounds

Question 39

What are the six function groups commonly attached to carbon atoms?

Answer 39

``` Amino Carboxyl Carbonyl Hydroxyl Phosphate Sulfhydryl ```