Final Review: Unit 4 Flashcards
1
Q
atoms
A
building blocks of matter
2
Q
nucleus
A
center of the atom
3
Q
protons
A
positively charged particles
4
Q
neutrons
A
neutrally charged particles
5
Q
electrons
A
negatively charged particles
6
Q
electron cloud surrounds
A
center of the atom
7
Q
atom charge
A
neutral
8
Q
elements
A
pure substances that cannot be broken down
9
Q
elements are made of
A
only one type of atom
10
Q
protons and electrons of elements
A
same number of each
11
Q
periods
A
horizonal rows
12
Q
groups
A
vertical columns
13
Q
how are elements grouped
A
if they have similar chemcial and physical properties
14
Q
atomic number is = to
A
of protons and electrons
15
Q
atoms have neutral charge because
A
protons = # electrons
16
Q
atomic mass
A
sum of the protons and neutrons in the nucleus
17
Q
where are protons and neutrons only found
A
nucleus
18
Q
isotopes
A
atoms of the same element with different numbers of neutrons
19
Q
isotopes of the same elements have
A
the same characteristics
20
Q
what affects the stability of the nucleus
A
change in the number of neutrons
21
Q
what does an unstable nucleus lead to
A
it decaying and emitting radiation
22
Q
what is an atom with a decaying nucleus called
A
radioactive isotope
23
Q
compounds
A
when two or more elements combine
24
Q
hydrocarbon
A
any compound made of only carbon and hydrogen
25
what ratio are compounds in
fixed
26
how to compounds differ from their original elements
chemically and physically
27
how to break down compounds
chemically
28
bonds
forces that hold substances together
29
what do bonds depend on
the number of electrons in the cloud
30
when do elements become more stable
when their shells are filled
31
covalent bonds
sharing of outer electrons between two elements
32
what bonds create molecules
covalent
33
single bond
shares one set of electrons
34
double bond
shares two sets of electrons
35
triple bond
shares 3 sets of electrons
36
ionic bonds
electrical attraction between two oppositely charged atoms
37
ion
atom that has lost or gained one or more electrons
38
why does an atom become an ion
because it carries a charge now
39
when an atom loses an electorn
it becomes positive
40
when an atom gains an electron
it becomes negative
41
valence electrons
outer electrons
42
ionic compounds are mostly
solid at room temperature
43
if ionic compounds are liquid at room temperature they are
environmentally friendly
44
van der Waals forces
an attraction force between positive and negative regions of a molecule
45
what does van der Waals force strength depend on
size of a molecule
46
what shape is water compound
bent
47
polar molecules
molecules that have an unequal distribution of charges
48
what are electrons in water more attracted to
oxygen's nucleus
49
charges of oxygen and hydrogen
slightly negative; slightly positive
50
hydrogen bonds are types of
electrostatic attractions and van der Waals force
51
why does surface tension occur
water molecules at the top are more tightly together because there is less to stick to
52
cohesion
particles are attracted to each other
53
adhesion
particles are attracted to other molecules
54
capillary action
ability of water to flow up a narrow space with no assistance
55
specific heat
the amount of heat to change a unit mass of substance by one degree in tempreature
56
why is specific heat important
keeps organisms warm in cold temperatures
57
what does water's high specific heat mean
a lot of energy is needed to heat and cool water
58
density
ice is less dense than liquid water
59
melting point
temperature that a solid melts into a liquid
60
when does ice melt
32 F or 0 C
61
why is water a universal solvent
it is capable of dissolving more substances than any other liquid
62
components of a solution
solute, solvent
63
solvent
substance doing the dissolving
64
solute
substance being dissolved
65
acid
a substance that releases a hydrogen ion when dissolved in water
66
bases
substance that releases hydroxide ions when dissolved in water
67
what determines the strength of an acid or base
amount of hydrogen or hydroxide ions in a solution
68
what is the pH scale
0-14
69
pH
the concentration of hydrogen ions
70
low pH means
acidic
71
high pH means
basic
72
the higher the pH the
lower the hydrogen ions
73
buffers
mixtures that react with acids and bases to keep pH in a particular range
74
electrons of carbon
6 with 4 valences
75
macromolecules
large molecules that form from smaller organic molecules
76
polymers
repeating identical units linked by covalent bonds
77
monomer
one of something
78
dimer
two of something
79
trimer
three of something
80
hydrolysis
when water is added to break a bond
81
dehydration synthesis
when water is removed to restore a bond
82
carbohydrates are made of
carbon hydrogen oxygen
83
ratio of carbs
1:2:1
84
role of carbs
short term energy storage, structural support
85
monomer of carbs
monosaccharide
86
two monosaccharides
disaccharide
87
many monosaccharides
polysaccharide
88
glycosidic bond/glycosidic linkage
a type of covalent bond that joins a carbohydrate molecule to another group
89
lipids are made of
mostly carbon and hydrogen, but also oxygen
90
role of lipids
long term energy storage, phospholipids
91
monomer of lipids
fatty acids and glycerol
92
saturated fats
single bonds, easily stackable, solid at room temperature
93
unsaturated fats
double bonds, harder to stack, liquid at room temperature
94
proteins are made of
carbon hydrogen oxygen nitrogen
95
protein role
nearly every bodily function, structural support, cell to cell transport, cell signaling, enzymes, controls cell growth, muscles, skin, hair
96
monomer of protein
amino acid
97
primary structure
amino acid
98
secondary structure
alpha helix or beta sheets
99
tertiary structure
alpha helix and beta sheets
100
quaternary structure
many tertiaries
101
nucleic acids are made of
carbon hydrogen oxygen nitrogen phosphorus
102
role of nucleic acids
store and transmit genetic information
103
monomer of nucleic acids
nucleotides
104
the most important form of energy for living things
chemical energy
105
what forms after chemical bonds of one substance are broken
a new substance
106
chemcial change
new substance is formed
107
physical change
same substance that has an altered appearance
108
reactant
starting material
109
product
new substance
110
activation energy
the energy needed to start a chemical reaction
111
endothermic reaction
when a reaction takes in energy to form bonds
112
exothermic reaction
when a reaction gives off energy as bonds are broken
113
enzymes
proteins that decrease the amount of energy needed to start a reaction
114
substrate
the substance on which the enzyme acts
115
reactants vs substrates
before vs during
116
active site
a large pocket on an enzyme that fits with the substrate
117
what factors effect enzymes
temperature, pH, concentration
118
denatured enzymes
enzymes that are not in the right conditions that no longer work
