Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Bio 190 > Ch.2 > Flashcards

Ch.2 Flashcards

1
Q

Atoms contain three types of particles, positively charge

A
  • Protons
  • Electrons
  • Neutrons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Within an atom’s structure, electrons can be found in cloud like

A

orbitals

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

Select all of the following that are true about atoms that have partially filled energy shells.

A
  • They can form compounds.

- They tend to share, lose, or gain electrons.

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

An atom’s atomic number is based on the number of

A

protons

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

Oxygen has eight protons, eight electrons, and eight neutrons. What is its atomic mass?

A

16

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

True or false: Electrons are found in the atom’s nucleus.

A

False

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

A mole of a certain substance has a number of particles equal to

A

12 g of carbon

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

An electron shell is composed of one or more

A

orbitals

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

Why is the atomic mass of carbon reported in the periodic table slightly greater than its predicted mass?

A

Because of the presence of a small amount of heavier isotopes

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

valence ______electrons enable chemical bonds to form among atoms.

A

Unpaired

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

An atom’s atomic number represents

A

the number of protons.

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

By mass, the most abundant element in living organisms is

A

oxygen

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

The chemical formula of glucose is C6H12O6. How many oxygen atoms are in one molecule of glucose?

A
  • 6
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The atomic mass numbers reported in the periodic table do not exactly match calculations based on protons and neutrons due to

A

the presence of different isotopes of the same element.

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

covalent bond is one in which a pair of electrons

A

is shared between two atoms.

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

What four elements are the most common in living organisms?

A
  • Hydrogen
  • Oxygen
  • Carbon
  • Nitrogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why are atoms likely to share electrons?

A

Because they have unfilled outer electron shells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A new element found on earth has four unpaired electrons in its outer shell. Predict the maximum number of bonds in which the new element can participate.

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

A covalent bond in which the atoms share electrons unequally is a(n)

A

polar covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Atoms share a pair of electrons when they form a(n)

A

covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which of the following statements are true of a polar covalent bond?

A
  • The two atoms in the bond share the electrons unequally.

- The atoms in the bond differ in electronegativity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which of the following covalent bonds are polar?

A
  • O-H

- N-H

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

According to the _______ rule, atoms tend to be most stable when their outer shells are filled; this can be accomplished by gaining, losing, or sharing ________.

A
  • Octet,

- electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The bond between the hydrogen atom and oxygen atom of separate water molecules is a(n)

A

Hydrogen Bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Nitrogen has three unpaired electrons in its outer shell. The maximum number of covalent bonds that a nitrogen atom can form with other atoms while still remaining uncharged is 
3
26
Van der Waals forces arise when
random electron movement creates short-lived attractions.
27
In a polar covalent bond, the shared electrons are closer to the nucleus of the atom with
greater electronegativity.
28
A Na+ ion forms when
a sodium atom loses an electron.
29
A(n) ______ bond is formed when two atoms of different electronegativities share electrons.
polar covalent
30
Which of the following covalent bonds are nonpolar?
- O-O | - H-H
31
An ionic bond forms when a positively charged ion, called a(n) _____, interacts with a negatively charged ion, called a(n) ____
- cation | - anion
32
Van der Waals interactions can form between
any atoms
33
Which of the following properties are shared by many chemical reactions that occur in cells?
- They often require a catalyst. - They tend to proceed toward equilibrium. - They require energy.
34
What type of bond forms when a cation with a positive charge interacts with an anion carrying a negative charge?
Ionic
35
Ionic Bond
- Bond between a cation and an anion
36
Hydrogen Bond
- bond between atoms and partial positive and partial negative charge
37
Polar covalent bond
Bond in which two atoms share electrons unequally
38
Non-polar covalent bond
Bond in which two atoms share electrons equally
39
Chemical reactions require a source of energy and also may require a substance called a(n)_____ that speeds up the reaction rate. Most chemical reactions proceed toward a state called, _____  in which the rate of product formation equals the rate of reaction forms
- enzyme | - equilibrium
40
Which of the following statements describe hydrophilic molecules?
They are soluble in water.
41
A(n) ______ bond is formed when two atoms of different electron-negativities share electrons.
polar covalent
42
Amphipathic molecules have both
- hydrophobic and hydrophilic
43
The amount of solute (in grams) dissolved in a given volume of solution is the solution
concentration
44
Which types of chemical bonds are easily broken in water?
- Ionic bonds | - Hydrogen bonds
45
The atomic mass of hydrogen is 1, and the atomic mass of oxygen is 16. What is the molecular mass of a water molecule (H2O)?
18
46
When water freezes
- water molecules are packed into a more orderly formation. | - the rate of hydrogen bond breakage slows.
47
Select all of the following that describe hydrophobic molecules.
- They are relatively insoluble in water | - They contain many nonpolar covalent bonds.
48
An amphipathic molecule
- has polar regions. | - has non-polar regions.
49
Water has a high heat of fusion. This means that
- much energy must be withdrawn to cause water to change from a liquid state to solid.
50
The concentration of a liquid is defined as the amount of ______ dissolved in a unit volume of solution.
- solute
51
The atomic mass of carbon is 12, and the atomic mass of hydrogen is 1. What is the molecular mass of a methane molecule (CH4)?
16
52
Polar covalent O-H bonds in water molecules enable hydrogen bonds to form between water molecules. Which of the following properties of water result from hydrogen bond formation?
``` Cohesion Adhesion Surface tension High specific heat High heat of vaporization ```
53
Which of the following contributes to water's stability in a liquid state?
- A high heat of fusion | - A high heat of vaporization
54
Pure water can ionize into
- positively charged protons (H+) and negatively charged hydroxide (OH-) ions.
55
High specific heat, surface tension, and cohesion are several properties of water involving 
hydrogen bonds
56
Sodium hydroxide is a base because when dissolved in water it binds _________ ions that are in solution.
hydrogen
57
The pH of a solution is defined as the ______ (base 10) of the hydrogen ion concentration
negative logarithm
58
Acidic
Contains more H+ than OH- ions
59
Alkaline:
Contains more OH- than H+ ions
60
Neutral:
Contains equal numbers of OH- and H+ ions
61
Living organisms minimize changes in their internal pH using compounds called
buffers
62
When water ionizes, it produces what ions? Select all that apply.
- OH– | - H+
63
Which substance is acidic?
stomach fluid
64
The ______ of a solution is the negative base 10 logarithm of the H+ concentration of the solution.
pH
65
Arrange the following solutions in order of increasing proton concentration. The solution with the lowest proton concentration should be placed at the top of the list.
- alkaline - Neutral - Acidic
66
What type(s) of compound(s) minimize pH fluctuations in the fluids of living organisms?
- buffer | - buffering agent
67
Living organisms minimize changes in their internal pH using compounds called
buffers

Bio 190 (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions