chem final Flashcards
1
Q
to convert from one resonance structure to another, _
A
only electrons can be moved
2
Q
elements _ exhibit similar physical and chemical properties
A
in the same group on the periodic table
3
Q
group periodic table
A
vertical and down (same physical and chemical properties)
4
Q
periods periodic table
A
across and horizontal and left to right
5
Q
the gold foil experiment performed in Rutherford’s lab _
A
led to the discovery of the atomic nucleus
6
Q
valence electron
A
the number of electrons on the outermost shell of an atom
7
Q
how do u find valence electrons?
A
the number at the top row
8
Q
alkali metals
A
group 1 metals
1 valence electron
highly reactive
soft (like butter)
low melting points
shiny
9
Q
alkaline earth metals
A
group 2 metals
2 valence electrons
very reactive but less than alkali metals
harder than alkali metals
higher melting point than alkali metals
metal luster shiny
10
Q
halogens
A
group 17
7 valence electrons
highly reactive
very colorful
11
Q
transition metals
A
group 3-12
vary in everything
valence electrons based on orbitals
12
Q
noble gasses
A
group 18
complete valence shell
highly stable
very unreactive
colorless, odorless, tasteless
low boiling and melting point
nonflammable
13
Q
metalloids
A
on the line thing
between metals and non metals
metallic luster but brittle
moderate electrical conductivity
low thermal conductivity
14
Q
nonmetals
A
right of metalloid line
15
Q
metals
A
left of metalloid line
16
Q
metalloid line
A
dividing line between metals and nonmetals
17
Q
electron configuration
A
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f14 6s2 6p6 6d10 7s2 7p6
18
Q
ionic
A
metal + non metal
19
Q
covalent
A
nonmetal + nonmetal
20
Q
anion
A
negative charge (right)
21
Q
cation
A
positive charge (left)
22
Q
how do u find number of electrons
A
atomic number (bottom left)
23
Q
how do u find mass number
A
protons + neutrons (top left)
24
Q
how do u find number of protons
A
atomic number (bottom left)
25
how do u find number of neutrons
mass number - atomic number
top left - bottom left
26
which is NOT one of the postulates of Dalton's atomic theory
atoms are composed of protons, neutrons, and electrons
27
which ARE some of the postulates of Dalton's atomic theory
-each element is composed of extremely small particles called atoms
-atoms of an element are not changed into different types of atoms by chemical reactions: atoms are neither created nor destroyed in chemical reactions
-compounds are formed when atoms of more than one element combine; a given compound always has the same relative number and kind of atoms
-all atoms of a given element are identical; the atoms of different elements are different and have different properties
28
each s-subshell can accommodate a maximum of _ electrons
2
29
if a mixture is uniform throughout and can be separated into other substances by physical means, it is _
a homogeneous mixture
30
homogeneous
same thru the whole mixture
31
heterogeneous
different thru the whole mixture
32
what type of change: tarnishing of silver
chemical
33
what type of change: dissolving sugar in water
physical
34
what type of change: crushing of stone
physical
35
what type of change: melting of lead
physical
36
what type of change: dropping a penny in a glass of water
physical
37
element
substance made up of one type of atom
38
compound
a substance that is made up of more than one type of atom bonded together
39
mixture
a combination of two or more elements or compounds which have not reacted to bond together
40
what type of change: chopping a log into sawdust
physical
41
what type of change: charging a cell phone
chemical
42
what type of change: burning a plastic water bottle
chemical
43
what type of change: the tarnishing of a copper penny
chemical
44
what type of change: the production of hydrogen gas from water
chemical
45
cathode rays are deflected away from a negatively charged plate, leading to the discovery of _
negatively charged particles
46
all atoms of a given element have the same _
number of protons
47
all atoms of a given element can have different _
density, mass, number of neutrons, and number of electrons
48
octet rule
atoms try to make their outer shell full
49
element-mass number
element
(top left - mass)
(bottom left - atomic number/number of protons)
(top right - charge)
50
sig fig rules
-All non-zero numbers ARE significant
-Zeros between two non-zero digits ARE significant
-Leading zeros are NOT significant
-Trailing zeros to the right of the decimal ARE significant
-Trailing zeros in a whole number with the decimal shown ARE significant
51
moles to grams
multiply by molar mass
52
grams to moles
divide by molar mass
53
going TO mole island
divide
54
leaving mole island
multiply
55
atom/molecule to mole
divide by 6.022 × 10²³
56
mole to atom/molecule
multiply by 6.022 × 10²³
57
liter/volume to mole
divide by 22.4L
58
mole to liter/volume
multiply by 22.4L
59
precision
how close a measured number is to other measured numbers
60
accuracy
how close a measure number is to the ACTUAL value
61
an empirical formula always indicates _
the simplest whole number ratio of different atoms in a compound
62
molecular formula
how many atoms of each element are in a compound
63
when a hydrocarbon burns in air, a compound produced is _
carbon dioxide and water
64
synthesis (types of reactions)
2 to 1
H + Cl --> HCl
65
decomposition (types of reactions)
1 to 2
HCl --> H + Cl
66
single replacement (types of reactions)
1 is changed around
AlCl + Br --> AlBr + Cl
67
double replacement (types of reactions)
2 are changed around
NaCl + KBr --> KCl + NaBr
68
combustion (types of reactions)
ANYTHING reacts with oxygen
69
King Henry Died By Drinking Chocolate Milk (0.001 --> 1000)
small to big
(remember to cancel out the units)
divide
243 / 100 cm = 2.43m
70
King Henry Died By Drinking Chocolate Milk (0.001 --> 1000)
big to small
(remember to cancel out the units)
multiply
243m x 100 cm = 24300cm
71
m/s --> km/hr
convert m to km
convert s to hr
72
how do u find the empirical formula?
1. divide each percent by the molar mass
2. divide the ending molar masses by the smallest molar mass
3. the number you get goes in the formula
EX: 3C, 6H, and 2O --> C3H6O2
73
how do u find the molecular formula?
1. take empirical formula
2. multiply by molar mass
3. add the molar masses together
4. use the given mass and divide it by the molar masses total
5. multiply the empirical formula by the answer in step 4
EX: (given-290g/mol)/(calculated thru steps 1-3(58.09g.mol)) = 5
5 x (C3H6O2) = C15 H30 O10
74
PV =
nRT
75
pressure x volume =
moles of gas x ideal gas constant (0.08206) x temperature in K (C + 273)
76
crystalline solids _
have highly ordered structures
77
sublimation
solid to gas
78
polar
lewis dot is not even, and its strong ish, dipole-dipole
79
if a lewis dot is even, and there are dots on the outside but not the inside, it is _
not polar
80
if a lewis dot is even, and there are dots in the middle but not the outside, it is _
polar
81
non polar
lewis dot is even, and its weak, london dispersion
82
strong to weak intermolecular forces
ionic, hydrogen, dipole-dipole, london dispersion
83
weak to strong intermolecular forces
london dispersion, dipole-dipole, hydrogen, ionic
84
ionic intermolecular force
metal and non metal, or + <--> -
85
hydrogen intermolecular force
Hydrogen + F, N, or O
86
dipole-dipole intermolecular force
polar = non even
<-- <--
--> -->
different charge everywhere
87
london dispersion intermolecular force
non polar = even
--> <--
<-- -->
same charge everywhere
88
how does atomic radius increase
left and down
89
how does electronegativity increase
up and right
90
how does ionizing energy increase
up and right
91
bent/angular
2 surrounding atoms
1 or 2 lone pairs
<120* if 1 lone pair
<109.5* if 2 lone pairs
92
trigonal pyramidal
3 surrounding atoms
1 lone pair
<109.5*
93
trigonal planar
3 surrounding atoms
0 lone pairs
120*
94
tetrahedral
4 surrounding atoms
0 lone pairs
109.5 degrees
95
linear
2 atoms
180*
2 surrounding atoms w/ 0 lone pairs
96
non polar covalent number
<0.3
97
polar covalent number
0.3 < x < 1.7
98
ionic number
1.7<
99
deposition
gas to solid
100
changing phases formula (straight line on graph)
q = n(ΔH)
q=heat
n=moles of substance
ΔH=mole enthalpy (energy per moles) KJ/mol
101
ΔH fusion number
6.02
102
fusion
melting / solid to liquid
103
ΔH freezing number
-6.02
104
ΔH vaporization number
40.6
105
ΔH condensation number
-40.6
106
changing temp formula (diagonal line on graph)
q = mCΔT
q=heat
m=mass in grams
C=heat capacity
ΔT=change in temp (final-initial)
107
water specific heat capacity number
4.184 J/gxC
108
one significant difference between gases and liquids is that _
a gas expands to fill its container
109
1 atm = _ torr
760
110
1 atm = _ mmHg
760
111
1 atm = _ psi
14.7
112
1 atm = _ kPa
101.325
113
pressure conversions formula
given x (transforming value / given value) = given transformed value
114
in liquids, the attractive molecular forces are _
strong enough to hold molecules relatively close together but not strong enough to keep molecules from moving past each other
115
the weakest interparticle attractions occur between particles of a _ and the strongest interparticle attractions exist between particles of a _
gas, solid
116
Avogadro's law
volume and number of moles in a gas are directly related
117
inversly related
one increase, other decrease
118
directly related
one increase, other increase
119
boyle's law
pressure and volume are inversely related
120
charles' law
volume and temp are directly related
121
Gay-Lussac's Law
pressure and temp are directly related
122
gas laws formula
PV/T = PV/T
123
gas laws formula: if it's multiplied, it is _ related
inversely
124
gas laws formula: if it's divided, it is _ related
directly
125
STP (standard temp & pressure)
273 K
1 atm
126
how do u do gas stoichiometry at STP?
g --> mol --> other element mole/current element mole --> volume (22.4L/1mol)
127
how do u do gas stoichiometry not at STP? (ideal gas law formula)
1. convert moles
2. V = nRT / P
V = volume
n = moles
R = 0.08206
T = temp in K
P = pressure
128
mole fraction / partial pressure formula
Xi = ni / ntotal
Xi = mole fraction
ni = # of mole component
ntotal = total # of moles
129
partial pressure formula
pressure A = ((volume B x pressure B) - (volume C x pressure C)) / volume A
130
beta particle
0 / -1 e
131
positron
0 / 1 e
132
emission
1 / 0 B
133
alpha
4 / 2 e
134
triple point
solid, liquid, and gas at the same time
135
supercritical fluid
liquid and gas at same time
136
molecules with stronger intermolecular forces have higher _ _
melting points
137
in general, as activation energy increases, reaction rate_
goes down regardless of whether the reaction is exothermic or endothermic
138
exothermic
releases heat
139
endothermic
absorbs heat
140
the reaction rate depends on _
all of the above
141
at equilibrium, _
the rates of the forward and reverse reactions are equal
142
first order reaction
k[element]^1
143
second order reaction
k[element]^2
144
the magnitudes of Kf and Kb depend on the identity of the _
solvent
145
the _ is the material that usually decides the solution's physical state (solid, liquid or gas)
solvent
A solution of salt and water, for example, has water as the solvent and salt as the solute.
146
the _ is the product that the solvent dissolves
solute
A solution of salt and water, for example, has water as the solvent and salt as the solute.
147
how do u write the equilibrium constant
products / reactants
148
specific heat capacity formula
q=mcAT
q=energy
m=mass in grams
c=specific heat capacity
AT=temp change
149
the phrase "like dissolves like" refers to the fact that _
polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes
150
∆S is _
entropy
151
∆H is _
enthalpy
152
in general, as temp goes down, reaction rate _
goes down regardless of whether the reaction is exothermic or endothermic
153
in general, as temp goes up, reaction rate _
goes up regardless of whether the reaction is exothermic or endothermic
154
If the volume of the container is increased (at constant T), the system will shift in the direction that _ the number of moles of gas in the container
increases
155
If the volume of the container is decreased (at constant T), the system will shift in the direction that _ the number of moles of gas in the container
decreases
156
catalyst
reactant --> product
157
intermediates
product --> reactant
158
how do u write rate law?
rate=k[A]^m[B]^n
k=rate constant
A and B=reactants
m and n=orders (how much they affect the reaction)
159
in general, as temperature goes up, reaction rate _
goes up regardless whether the reaction is exothermic or endothermic
160
in general, as temperature goes down, reaction rate _
goes down regardless whether the reaction is exothermic or endothermic
161
solution
everything is even
homogenous
162
solute + solvent =
solution
163
what affects dissolving rate?
surface area - substance pulls apart more
stirring - clears dissolved particles out of way and allows water to pull apart rest of substance
temp - high temp means molecules move faster and can pull apart faster
164
concentration
how strong a solution is, and how much has been dissolved
165
dilute solution
not much has been dissolved
166
concentrated solution
a lot has been dissolved
167
molarity definition
amount of moles that have been dissolved in a specific volume of a solution
168
molarity formula
moles of solute / liters of solution
mol / L
169
dilution formula
M1V1 = M2V2
M = molarity
V = volume
170
a solid is formed
known as precipiate
171
When two solutions are mixed, there are a few signs that a reaction has actually occurred:
a solid, gas, or liquid is formed
172
soluble
dissolves in water
aka dissociation
173
insoluble
doesn't dissolve in water
stays as a solid
174
Colligative properties
properties that depend on the concentration of the solute dissolved in solvent and that will change the normal properties of the solvent
175
Freezing Point Depression
By adding a solute to water, the water will now have a lower freezing point
176
Boiling Point Elevation
By adding a solute to water, the water will now have a higher boiling point
177
Electrolytes
substance that dissolve into their separate ions and allow water to conduct electricity (ionic)
178
Non-electrolytes
substances that dissolve, but do not break into different ions (covalent) (i=1 always)
179
freezing point depression formula
∆t = Kf x m x i
∆t = change in freezing point
Kf = -1.86 (freezing point constant for water)
i = van hoff's factor (number of particles)
m = molality
180
boiling point elevation formula
∆t = Kb x m x i
∆t = change in temp
Kb = boiling point constant for water (0.51)
i = number of particles
181
reversible reactions
can go in both directions
182
if Keq < 1 and Q > K, _ is favored
reverse reaction
more reactants than products
183
if Keq > 1 and Q < K, _ is favored
forward reaction
more products than reactants
184
if Q = K, the reaction _
is at equilibrium
185
Le Chatelier’s Principle states
a system will always try to be at equilibrium
186
what are the 3 ways to stress a system?
change pressure, concentration, or temp
187
changing the pressure only affects the system if there is a _
gas
188
if the pressure increase, the volume will _
decrease
With less volume, the system will move to the side of the reaction that has fewer moles of gas
189
if the pressure decrease, the volume will _
increase
With a larger volume, the system will move to the side that has more moles of gas
190
if we increase concentration, there is _ of a substance. the reaction moves in the direction that uses up the _
extra
191
if we decrease concentration, there is no longer _ of that substance. the reaction moves in the direction to replace the ) substance
enough, missing
192
temperature: exothermic
energy is a _
product
193
temperature: endothermic
energy is a _
reactant
194
decrease temp changes how much _ there is. we do the same thing as with _
energy
concentration
195
aq solutions are when ions get _
separated
196
In order for a reaction to occur, the molecules must _ in the correct orientation and with enough energy to break the bonds. Once the bonds are broken, new bonds can be formed and a new molecule is made
The energy required to do this is called _ _
collide
activation energy
197
what are the several factors that determine how quickly a reaction will take place?
nature of reactants
surface area
temp
concentration
198
rate laws are used to determine how _ a reaction can take place
quickly
199
Energy flows in or out of a reaction because
molecules require energy to keep the atoms bonded together
200
negative ΔH means energy is lost by the system, or is _
exothermic
201
positive ΔH means energy is gained by the system, or is _
endothermic
202
activation energy (Ea)
Minimum energy required for particles to collide and react
203
catalyst
speeds up reaction
204
Many reactions do not happen in one single step, but instead require multiple reactions to get the desired results is who's law?
hess's law
205
rate determining step
slowest step in reaction
206
slowest step in diagram has highest
activation energy
207
the entropy of a pure crystalline substance at absolute zero is _
0
208
entrophy meaning
the measure of randomness in a system
209
standard entropies increase with _
molar mass and number of atoms
210
For a reaction to be spontaneous, it means that the reaction can happen without any _
outside influence
211
In order for a reaction to be spontaneous, ∆Suniverse must be
positive
212
∆G means _
Gibb's free energy
213
214
∆G formula
∆G = ∆H - T∆S
free energy = enthalpy - temp in K x entropy
215
whats an acid?
a substance that has an H+ ion
216
whats a base?
produces OH- and accepts H+
217
what are Conjugate pairs?
shows us how a reactant changes to become a product (follow the anion)
218
conjugate base
the substance created after H+ has been donated (removed)
anion of acid
paired with acid
219
conjugate acid
the substance created after H+ has been accepted (added)
made from base
paired with base
220
_ has a pH of 7
pure water
221
< 7pH
acidic
more hydrogen
222
> 7pH
basic
more hydroxide
223
A strong acid produces a _ conjugate base
We say the _ reaction is favored
weak
forward
224
A weak acid produces a _ conjugate base
We say the _ reaction is favored
strong
reverse
225
Titration
is a controlled addition and measurement of a solution with a known concentration to react with a solution of unknown concentration
226
Standard solution
a solution in which we know the concentration
227
Equivalence point
point at which there are equal amounts of moles of each solution
228
Endpoint
the point in the titration where the indicator has changed color
229
Indicator
a substance used to show when the is a change in pH (going from basic to acidic or from acidic to basic)
Most common is phenolphthalein
Turns pink when solution becomes basic
230
Electrochemistry
the study of the relationships between electricity and chemical reactions
231
chemical cell
a battery, where two different metals are used.
One metal will oxidized and the other metal will be reduced.
A battery “dies” when this process can no longer be continued.
232
redox reaction
one substance undergoes reduction and the second substance is oxidized, both of which happen because of a change in number of electrons
233
If the oxidation number decreases for an element, that element is _
reduced
234
If the oxidation number increases for an element, that element is _
oxidized
235
oxidation numbers: elements, not ion form
0
236
oxidation numbers: monatomic ion (ion of one type of atom
charge
237
oxidation numbers: F (when in a compound)
-1
238
oxidation numbers: O
–2 (unless peroxide = –1) (when in a compound)
**you know it’s peroxide based on the cation it is bonded with**
239
oxidation numbers: H
+1 (unless a metal hydride = –1) (when in a compound)
240
The sum of the oxidation numbers equals the overall charge:
(0 in a compound)
241
a species is _ when it loses electrons
oxidized
242
a species is _ when it gains electrons
reduced
243
how do u balance redox equations
1. make 2 half reactions (oxidation and reduction)
2. balance the atoms other than O and H first
3. balance O using H2O and H using H+
4. add electrons to balance charges
5. Multiply by common factor
to make electrons in half-
reactions equal.
6. Add the half-reactions.
7. Simplify by dividing by common factor if necessary.
8. Double-check atoms and charges balance!
244
voltaic cell other name
galvanic cell
245
voltaic cell oxidation occurs at the _
anode
246
voltaic cell reduction occurs at the _
cathode
247
voltaic cell meaning
a device that generates electrical energy thru a chemical reaction
248
_ are formed in the anode compartment as the metal dissolves
cations
249
As the electrons reach the cathode, cations in solution are attracted to
the now negative _
cathode
250
The potential difference between the anode and cathode in a cell is called the _.
It is also called the cell potential and is designated Ecell.
For a spontaneous cell, the cell potential must be positive
electromotive force
EMF
measured in volts (V)
251
The more positive the value, the more likely the reaction is to occur as written
So to decide which substance is more likely to reduce, look for the one with the larger _
E°
252
The cell potential at standard conditions can be found through this equation:
Ecell = Ered (cathode) – Ered (anode)
