Chapter 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What are atoms composed of?

A
  1. ) Nucleus: contains neutrons and protons

2. ) Electrons orbiting in the cloud

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Atoms Mass#=?

A

protons + neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Atoms atomic #=?

A

protons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the most abundant biological elements?

A

Carbon, oxygen, hydrogen, nitrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

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

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Valence:

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Ionic vs. Covalent bond?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When do ionic bonds typically occur?

A

When there is a large variance in electronegativity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When do covalent bonds typically occur?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

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

A

O»N>C=H

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Bond dissociation energy?

A

energy needed to break a bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

potential energy?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

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

A

bond dissociation energy increases and potential energy decreases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

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

A

bond dissociation energy decreases and potential energy increases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe Hydrogen bonds?

A
  • 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.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

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

A
  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
17
Q

PH scale:

A

The scale showing the amount of dissolved protons in a solution

18
Q

How to acids and bases differ in proton concentration?

A
Acids= higher proton concentration
Bases= lower proton concentration
19
Q

What is the equation to determine PH?

A

pH=-log{H+}

20
Q

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

A

{H+}= antilog(-ph)

21
Q

What does Ph serve to do?

A

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

22
Q

What is a buffer?

What is the example mentioned in lecture?

A

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

23
Q

What is the example of a buffer mentioned in lecture?

A

CO2 + H2O –>

24
Q

Potential energy?

A

Stored energy (chemical)

25
Q

Kinetic energy?

A

energy of motion (thermal energy)

26
Q

What is Gibbs Free energy (g)?

A

Free energy change associated with a chemical reaction

27
Q

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

A
DeltaG= DeltaH - T * DeltaS
DeltaG = change in Gibbs Free energy
DeltaH = change in enthalpy
T = temperature
DeltaS = change in entrophy or randomness
28
Q

What does it mean if DeltaG < 0 ?

What does it mean if DeltaG > 0 ?

A
  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
29
Q

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

A

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.

30
Q

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

A

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

31
Q

What was the problem with CO2?

A

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

32
Q

What are REDOX reactions?

A

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

33
Q

What does reduced mean?

A

Gains electrons

34
Q

What was Stanley Miller known for?

A

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

35
Q

Where did energy in the atmosphere come from?

A

Sun

36
Q

What are Free Radius atoms?

A

atoms or molecules that contain highly reactive unpaired molecules

37
Q

what is the probiotic soup model?

A
  • 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.
38
Q

What is the surface metabolism model?

A
  • 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
39
Q

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

A
Amino
Carboxyl
Carbonyl
Hydroxyl
Phosphate
Sulfhydryl