Chapter 2/3 - Molecules Flashcards
(200 cards)
1
Q
Any substance in the universe that has mass and occupies space
A
Matter
2
Q
Small particles that make up matter
A
Atoms
3
Q
Tunneling microscopy
A
Technology used to locate atoms
4
Q
What located at the center of an atom?
A
Nucleus
5
Q
What subatomic particles form the nucleus?
A
Protons and neutrons
6
Q
What subatomic particles surround an atom?
A
Electrons
7
Q
Electrons are found in
A
Orbitals
8
Q
Orbitals surround the
A
Nucleus of an atom
9
Q
Region within an atom where the electron will most likely be located
A
Orbital
10
Q
How many electrons can an orbital contain
A
2
11
Q
Atomic theory
A
- Every atom contains electrons
2. Protons and neutrons are at the core of an atom
12
Q
What charge does a proton have?
A
Positive
13
Q
What charge does an electron have?
A
Negative
14
Q
What charge does a neutron have?
A
No charge
15
Q
Any substance that cannot be broken down into any other substances by ordinary chemical means
A
Element
16
Q
Atomic number is equal to the number of
A
Protons
17
Q
True or False
Atoms with the same atomic number belong to the same element
A
True
18
Q
True or False
Different atoms have the same number of protons
A
False
Different atoms have a different number of protons
19
Q
Pure substance that contains one atom
A
Element
20
Q
True or false
Our body is made up of elements
A
True
21
Q
Oxygen has eight protons so that atomic mass is
A
8
22
Q
The atomic mass is equal to
A
Protons plus neutrons
23
Q
Which subatomic particles contribute to mass
A
Protons and neutrons
24
Q
True or false
Electrons contribute to mass and are heavier than protons and neutrons
A
False
Electrons do not contribute to mass and are not heavier than protons or neutrons
25
An atom is generally neutrally charged when
Where is an equal number of protons and electrons
26
Keeps electrons in their orbitals but opposite charge attraction
Protons
27
Can be gained or lost, turning into an ion
Electrons
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Ion
When the number of electrons does not equal the number of protons
29
Name two types of ions
Cation
| Anion
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Cation
1. Positive charge ion
| 2. Contains more protons than electrons
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Anion
1. Negative charge ion
| 2. Less protons than electrons
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True or false
Typically, an atom has one electron for each proton and is thus electrically neutral
True
33
The chemical behavior of an atom is due to the number and configuration of
Electrons
34
Positive charges in the nucleus of an atoms are neutralized by
Negatively charged electrons
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Isotope
Different form of the same element that possesses the same number of protons but different number of neutrons
36
The mass of atoms and subatomic particles is measured in units called
Daltons
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A proton weighs approximately
1.007 Dalton
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A neutron weighs approximately
1.009 dalton
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Electrons weigh
1/1840 of a dalton, so they contribute almost nothing to the overall mass of an atom
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Na , Cl
Na+ ---> Cl-
Which element is a cation/ which is an anion? Explain.
Na+ is the cation. It shared/lost its electron to Cl-. Giving it more protons than electrons. Thus, the positive charge.
Cl- is the anion. A gain an electron from an Na+. Giving it more electrons than protons. Thus, the negative charge.
41
Hydrogen has 1 proton, 0 neutrons.
Deuterium has 1 proton, 2 neutrons.
Tritium has 1 proton, 3 neutrons.
What is being described?
An isotope.
Same element possessing the same number of protons but different number of neutrons.
42
Radioactive isotope
- Unstable isotopes that will break down into an atom with a lower number of neutrons and or atomic number
- Undergoes radioactive decay
- release energy
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Radioactive decay
Unstable isotope that decays to an element with a lower atomic number
44
True or False
Some radioactive isotopes are more unstable than others
True
45
The decay time for a radioactive isotope is expressed as
Half life
46
The time it takes for 1/2 of the atom in a sample to decay
Half life
100%. Vs. 50%
Ex: 12C --- > Half Life = 7C
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How are fossils dated?
Through radioactive decay
48
Emits large quantities of energy that are harmful to living cells
Radioactive decay
49
Determines the chemical behavior of an atom
Electrons
50
What shapes are ORBITALS known to have
Spherical
Dumbbell shaped
51
Describe the 1s orbital
1. Closest to the nucleus of an atom
| 2. Lowest energy level
52
Describe 2s, 2p orbital
1. Further away from the nucleus of an atom
2. Second lowest energy level
3. 2s = 2 electrons
4. 2p = 3 orbitals
****Max of eight electrons
53
Name all energy levels alphabetically from lowest to highest
1. K ----> lowest (1s)
2. L (2s;2p)
3. M
4. N ----> highest
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How can you move electrons away from the nucleus?
Add energy
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How can you move electrons closer to the nucleus?
Release energy
56
When energy is released electrons move
Closer to the nucleus -----> because energy at lower orbitals contain less energy than orbitals further away from the nucleus
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When energy is absorbed electrons move
Further away from the nucleus, or the outer orbital
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What energy level is closest to the nucleus and which is furthest?
Close , K
Far , N
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- How many electrons can the outer most energy level contain?
- Name two exceptions.
- 8
| - He, H ----> Each contains a 1s orbital ONLY.
60
How can you increase the potential energy of an electron
Input energy
61
The amount of energy and electron possesses it is related to its distance from
The nucleus
62
Electrons that are the same distance from the nucleus have the same
Energy
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Oxidation
Transfer/Loss of an electron by an atom or molecule, in metabolism
Usually associated with the gain of oxygen or loss of hydrogen
64
Reduction
Gain of electron
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Redox Reaction
An atom or molecule becomes oxidized, while another is reduced in the same reaction
66
How many naturally occurring elements are there?
90
Each w different number of protons and a different arrangement of electrons
67
True or false
Elements have a repeating pattern of 6 elements
False
Elements have a repeating pattern of eight elements
68
Electrons in the outer most energy level are called
Valance electrons
69
Nonreactive/ Inert / "Happy"
Elements that contain all eight valance electrons in their outer most energy level
70
If an element contains all eight electrons in its outer most energy level can it bond with other elements
No because it is non-reactive, happy or inert
71
Elements that contain less than eight electrons are
Very reactive
72
Elements that contain seven electrons will try to
Fill up their outer most energy level
73
Elements that contain one electron will try to
Rid there outermost electron
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What is it called when one element loses its electron to another element
Ionic bond
75
Octet rule
Atoms like to completely fill their outer energy levels
76
If helium has two valance electrons and nitrogen has four valance electrons, which element would be very reactive?
Helium is non-reactive due to its 1s orbital, therefore nitrogen would be very reactive
77
What 12 elements are found in living organisms?
C, H, O, N, P, S, Na, K, Ca, Mg, Fe, Cl
78
Which elements make up 96.3% of your bodyweight?
C, H, O, N
79
Compounds found in living organisms that contain carbon
Organic compounds
80
Carbon is found in
Sugars, fatty acids, and amino acids
81
What does the Periodic Table display
Elements according to atomic number and properties
82
K has 1 valence electron/Br has 7 valence electrons. Based on the octet rule which element will be oxidized and which will be reduced? Explain.
K will be oxidized. It is very reactive and will rid its 1 valence electron.
Br will be reduced. It also is very reactive and will gain an electron from K instead of getting rid of its 7 valence electrons.
83
True or false
All noble gases are non-reactive
True
84
Majority of molecules that make up your body
Organic compounds
85
A group of atoms held together by energy and a stable association is called a
Molecule
86
ELEMENT Na has lost an electron to ELEMENT Cl, what type of bond is this?
Ionic bond
87
When a molecule contains atoms of more than one element it is called
A compound
88
When to or more elements are joined
Chemical bond
89
How can an ionic bond or lattice be broken?
In the presence of water/ or present water/ H2O
***ex: Na+ , Cl-
Na+ and CL- are attracted to the opposite poles of water, this allows Na to retain its + charge and Cl to retain its - charge
90
What bond that forms a Crystal, Solid, or lattice?
Ionic bond
91
Covalent bond
When 2 atoms share a valance electron
Or
When 2 or more atoms share one or more pairs of electrons
92
Forms when atoms with opposite electrical charges (ions) attract
(+)Cation ^ Anion(-)
Ionic bonds
93
True or false
NaCl is common table salt
True
Lattice, solid, crystal
94
Are covalent bond stable? Explain.
Yes, covalent bond are stable.
1. NO NET CHARGE, so neither atom loses or gains electrons
2. SATISFIES OCTET RULE, shared electrons can orbit both atoms.
3. HAS NO UNPAIRED ELECTRONS , free electrons shared between two atoms are now paired.
95
Do double bonds satisfy the octet rule?
Yes, by allowing to atoms to share two pairs of electrons
96
True or false
The strength of covalent bond depends on the number of shared electrons
True
Ex: Triple bond > double bond > single bond
97
In a covalent bond what does — represent?
The sharing of one electron pair
98
How many valence electrons does carbon have?
4
99
Carbon can form multiple covalent bonds because it has
Four valance electrons
100
Affinity for electrons
Electronegativity
101
Increases left to right across a row of the periodic table and decreases down the column
Electronegativity
102
Nonpolar covalent bond
1. Affinity for electrons is the same, the electrons are equally shared.
2. Equal electronegativity
****Neither element is pulling the electrons more than the other because equal electronegativity
**** Same element
**** different elements with a very similar electronegativity
103
Polar covalent bond
Unequal electronegativity
Electrons are not shared equally
Atoms differ greatly in electronegativity
Shared electrons are more likely to be closer to the atom with greater electronegativity and less likely to be near the atom of lower electronegativity
Electrically neutral
104
Contains regions of partial negative charge near the more electronegative atom
Polar covalent bonds
105
Contains regions of partial positive charge near the less electronegative atom
Polar covalent bond
106
Formation or breaking of chemical bonds
Chemical reaction
107
What are chemical reactions to dependent on?
1. Temperature, which affects the speed of molecular movements
2. Centration of products or reactants,
More reactant = more reaction
Less reactant = less reactant
3. Catalysts
Speeds the rate of reactions
108
What protein catalyzes almost every chemical reaction in living systems
Enzymes
109
Consist of 2H covalently bonded to 10
Water
110
True or false
Water is not stable
False
Water is very stable
1. Satisfies octet rule
2. All electrons paired
3. Carries no net electrical charge
111
Which has a higher electronegativity, oxygen or hydrogen?
Oxygen
112
Is a water molecule polar or nonpolar?
Polar
113
H2O carries two partial negative charges near
Oxygen
114
H2O carries to partial positive charges on
Each hydrogen
115
High polarity of water allows formation of
Hydrogen bonds
116
True or false
Hydrogen bonds organize most of the molecules in living systems
True
117
Bonds between partially negative O atoms and the partially positive H atoms of two water molecules form
Hydrogen bonds
118
Since water molecules attract each other they are
Cohesive
119
Because water molecules are attracted to other polar molecules they are
Adhesive
120
True or false
The polarity of water allows water molecules to be attracted to one another
True
Water is cohesive
121
What is responsible for water being a liquid and not a gas
Waters cohesion
122
True or false
The polarity of water allows it to be attracted to other polar molecules
True
Water is adhesive
123
Specific heat
The amount of heat needed to be absorbed or lost by 2g of a substance to raise or lower is the temperature by 1°C
124
How much energy do you need to put into a substance to raise or lower its temperature?
This question describes what.
Specific heat
125
Heat of vaporization
The amount of heat needed to change a liquid to a gas
126
How much heat do you need to put into change that substance from a liquid to a gas
The question is an example of what.
Heat of vaporization
127
Does water have a high specific heat
Yes
Due to its unique nature in forming hydrogen bonds
128
Partial + and Partial - allow water to form
Hydrogen bonds
129
How can a hydrogen bond be broken
By an abundance of thermal energy or heat
130
Does water take awhile to heat up?
Yes, because it has a high specific heat so you need a lot of heat to heat up water
131
Biological systems/living organisms are mostly composed of water which helps to maintain
Body temperature
132
Biological reaction
- Produces heat
| - Transfers heat to surrounding water ( breaks a couple hydrogen bonds )
133
Overheating and biological systems is possible without the presence of
Water
134
Does water have a high heat of vaporization?
Yes.
As he is released from the body, any water to the surface of the body, he will break down does hydrogen bonds, water will evaporize to air.
Ex: Too hot----> sweat
135
Do polar ions carry a charge?
Yes.
Anion / cation
136
Is a polar ion soluble in water?
Yes
137
True or false
Water is not attracted to polar ions
False
Water is attracted to polar ions
138
Water surrounds ions to form
Hydrogen bonds within a water molecule
139
Is water a solute, or solvent?
Solvent
140
Are ions solute or solvent?
Solute
****Soluble in water
141
Polar ions want all of their surface exposed to water therefore they are
Hydrophilic
142
Oil is an example of what type of molecule
Non-polar molecule because it is hydrophobic, water fearing
143
Aggregate, or clumps together to minimize their disruption of hydrogen bonding in water
Nonpolar molecules
Because they are hydrophobic, water fearing
144
What does water cause nonpolar molecules, such as oil to do
Aggregate, or push together
145
What determines the PH of a solution?
Concentration of H+ and OH-
146
PH measures
The # or concentration of protons and hydrogen ions
147
Based on a Ph scale
0=
7=
14=
0 is most acidic
7 is neutral
14 is most basic
148
Substance resistant to PH change
Buffer
149
What does a buffer do when pH is too high or acidic
Releases H+
150
What does a buffer do when pH is too low or basic
Absorbs H+
151
Maintains constant pH
Buffer
152
Substance that dissolves in water to increase H+ concentration
Acid
153
A substance that combines with H+ when dissolved in water, thus lowering H+
Base
154
True or false
Living organisms are not sensitive to pH change
False
living organisms are very sensitive to pH change
155
Blood pH is maintained by which to buffers
Carbonic acid
Bicarbonate
156
True or false
The pH inside almost all living cells, and in the fluid surrounding cells in multicellular organisms,is fairly close to neutral, 7.
True
157
Is CO2 basic?
No. CO2 is acidic
158
In our bodies CO2 is converted to
Bicarbonate
159
What does bicarbonate do in our body
Transfers CO2 to the lungs so that we can breathe it out
160
If blood is too acidic bicarbonate will add or retain a_________________ to form _____________________.
Proton
Carbonic acid
161
If too basic carbonic acid can release a____________ to form ________________.
Proton
Bicarbonate
162
Can form chemical compounds
Are chemically reactive
Can form bonds with other atoms
Atoms that have unfilled electrons cells
163
Arrange states of water from most dense to least dense
Sold
Liquid
Gas
Liquid - water is more dense than ice
Solid (ice)
Gas
164
Made of two or more atoms held together by chemical bonds and stable association. The Atoms may or may not belong to the same element
Molecule
165
Arrange least to greatest based on electronegativity
| H,C,O,N
H
C
N
O
166
Van der waals attraction
Weak attraction between atoms due to oppositely polarized electron clouds
167
Attraction between covalently bound H atom with a slight positive charge and another covalently bound atom with a slight negative charge
Hydrogen bond
168
Hydrophobic interaction
Nonpolar regions of a molecule are forced together in order to minimize contact with water molecules
169
Elements possessing all 8 valence electrons are said to be
Inert
Noble gases
170
Rank the following bonds and interactions in order from strongest to weakest starting with the strongest at the top
```
Ionic bond
Hydrogen bond
Covalent bond
Van der walls attraction
Hydrophobic interaction
```
Covalent bond
Ionic bond
Hydrogen bond
Hydrophobic interaction
Van der waals attraction
171
Cohesion
Plant leaves pull water up from roots
172
Many types of ions and molecules move freely in cells, permitting a diverse array of chemical reactions
Solubility
173
Why is H2 stable? (, a molecule formed by two hydrogen atoms )
Held together by covalent bond
No net charge
No unpaired electrons
174
Water is polar
True or false
True
175
O2, CH4, N2 are all nonpolar
True or false
True
176
Hydrogen atoms always have one proton
True/false
True
177
Ex: molecular formula
H2
178
Elements in the same chemical group have the same bonding properties because they have the same number of valance electrons
True/false
True
179
The number in configuration of electrons determine and elements
Chemical properties
180
Hydrogen < single covalent < double covalent < triple covalent
These bonds are arranged from weakest to strongest
True or false
True
181
Chemical bonds are broken and new bonds are formed on a
Chemical reaction
182
One____________ of the element carbon contains 6.02 x 10^23 atoms of carbon
Mole
183
The pH up of the solution is defined as
The negative logarithm of the hydrogen ion concentration in the solution
184
For most of the on the elements in living organisms
Hydrogen ,oxygen , nitrogen and carbon
185
Water rises inside a glass tube with narrow diameter due to
Water molecules adhere to the surface of the glass
186
Element
Substance that cannot be broken down into simpler substances by ordinary chemical means
187
Trace elements
Present in tiny amounts
Play cry or ole in living processes
188
The ability of water to rise inside a tube of narrow diameter against the pull of gravity is called
Capillary action
189
Dalton =
Atomic mass
190
Surface tension of what is due to
The cohesion of water molecules
191
The property of ______________ is a measure of how difficult it is to stretch or break the surface of a liquid
Surface tension
192
Polar molecules
Attracted to other polar molecules
Electrically neutral
Same number of protons and electrons
193
When writing out structural formulas, covalent bonds are represented by the
Lines between atomic symbols
194
Hydrogen bond can form between partial negative ___________ atom of one water molecule and partial positive ___________ atom of another molecule
Oxygen
Hydrogen
195
Non polar covalent bond
Equal sharing of one or more pairs of electrons
196
Hydrocarbon chains are considered nonpolar
True
197
Buffers stabilize pH by releasing hydrogen ions when a base is added and absorbing hydrogen ions when an acid is added
True
198
Bond formed between two hydrogen atoms
Nonpolar covalent
199
A substance whose molecules are made of atoms of more than one element held together by chemical bonds is called
Compound
200
Ionic compounds generally exist as individual ions
True
