Exam 1 Flashcards
1
Q
scientific notation: Measurement
A
- QUANTITATIVE observation
- uses numbers and units
- numbers tells MAGNITUDE
- unit tells SCALE (unit is slightly more important than #)
- expresses a # as a product of a # between 1 and 10 and the appropriate power of 10
ex: 93,000,000 = 9.3 x 10,000,000 = 9.3 x 10^7
2
Q
10^x
move decimal to the LEFT, exponent is __; move decimal to the RIGHT, exponent is ___
A
positive (+); negative (-)
3
Q
using scientific notation examples
A
345 = 3.45 x 10^2 0.0671 = 6.71 x 10^-2 7882 = 7.882 x 10^3 0.0000496 = 4.96 x 10^-5
4
Q
unit
A
the scale/standard being used to represent the results of a measurement
- most common systems: English and metric systems
- internation system (SI)
5
Q
internation system (SI)
A
- comprehensive system of units set up by an international agreement
- units based and derived from metric system
6
Q
fundamental SI units
A
PHYSICAL QUANTITY UNIT
Mass kg
Length m
Time second
Temp. Kelvin
electric current ampere
amnt. of substance mole
7
Q
commonly used prefixes in metric system
A
prefix symbol meaning power of 10
mega M 1,000,000 10^6
kilo k 1000 10^3
deci d 0.1 10^-1
centi c 0.01 10^-2
milli m 0.001 10^-3
micro μ 0.000001 10^-6
nano n 0.000000001 10^-9
8
Q
volume
A
- measures 3D space by a substance
- SI unit = m^3
- commonly measured cm^3
- 1 mL= 1 cm^3
- 1 L= 1 dm^3
9
Q
1 mL= _ cm^3
A
1
10
Q
1 L= _ dm^3
A
1
11
Q
length
A
-fundamental SI unit is meter unit meter equivalent km 1000 m or 10^3 m m 1 m dm 0.1 m or 10^-1 m cm 0.01 m or 10^-2 m mm 0.001 m or 10^-3 m μm 0.000001 or 10^-6 m nm 0.000000001 or 10^-9
12
Q
mass
A
-measures matter present in object
-SI unit is kg
1 kg= 2.2046 Ibs
1 Ib= 453.59 g
13
Q
use __ __ to measure uncertainty
A
sig figs
14
Q
rules for sig figs
A
1) all nonzero integers ALWAYS count for significance ex: 3456 has 4 sig figs
2) zeros (3 classes of zeros)
a) leading zeros:NEVER count as sig figs
ex: 0.048 has 2 sig figs
b) captive zeros: ALWAYS count as sig figs ex: 16.07 has 4 sig figs
c) trailing zeros: only significant when # HAS A DECIMAL POINT
ex: 9.300 has 4 sig figs; 0.004020 has 4 sig figs; 150 has 2 sig figs
15
Q
sig figs for x and ÷
A
the # of sig figs for answer is LEAST amount of sig figs u have in the problem
ex: 1.342 x 5.5 = 7.4
* when solving many calculations for 1 problem, don’t convert sig figs until LAST STEP
16
Q
sig figs for + and -
A
only count decimal places
ex: 23.445 + 7.83 = 31.275 = 31.28
ex: 101 + 1.0 = 102
- always solve from left to right
17
Q
sig fig question:
4.56 x 7.3679 / 1.006 =
A
- multiply first, then divide, then find sig figs
answer: 33.4
18
Q
exponential notation/scientific notation
A
ex: 300 as 3.00 x 10^2 contains 3 sig figs
- advantages
a) # of sig figs can be easily indicated
b) fewer zeros needed to write a very large/very small #
19
Q
rounding rules
A
when doing many calculations, carry extra digits thru until final result and then round
20
Q
3 units for measuring temp
A
1) ºF
2) ºC
3) Kelvin (K)
21
Q
3 major temp scales
A
Farenheit
boiling pt: 212ºF
freezing pt: 32ºF
Celsius
boiling pt: 100ºC
freezing pt: 0ºC
Kelvin
boiling pt: 373 K
freezing pt: 273 K
22
Q
converting between temp scales
A
Tk= TºC +273 TºC= Tk-273 TºC= (TºF - 32/1.80) TºF= 1.80(TºC)+32
23
Q
K to ºC is
A
-273
24
Q
density
A
density =mass/volume or D=m/V
- mass of substance per unit volume of substance
- common units: g/mL or g/cm^3
- when mass increases, density increases (directly proportional)
- when mass is constant and volume decreases, density increases (inversely proportional)
25
when does ºC = ºF?
```
x= ºC and ºF
x= 1.80x+32
x-32=1.80x
-32=1.80x-x
-32=x(1.80-1)
x=-32/.80
x=-40
**at -40, ºC=ºF**
```
26
matter
- anything occupying space and having mass
- matter exists in 3 states: s, l, q, and plasma
- the world is made up of matter and e
27
solid
- rigid
- doesn't change shape
- has a fixed volume and shape
- ex: ice cube, rock, diamond, phones, chair
28
liquid
- has a definite volume
- will take shape of container
- ex: car gas, water, alcohol, blood, ocean
29
gas
- no fixed volume or shape
- takes shape and volume of a container
- ex: air, helium, O2, atmosphere
30
plasma
gas so supercharged that it has liquid
| ex: lightning, comets, neon signs
31
physical properties
- characteristic that are directly observable and unique to a substance
- ex: odor, volume, color, state (s,l,g,p), density, boiling pt, melting pt
32
chemical properties
- a substance's ability to make new substances
- characteristics that determine how the composition of matter changes as a result of contact w/ other matter/influence of e
- characteristics that describe behavior of matter
- ex: flammability, rusting of steel, toxicity, enthalpy, chemical stability, reactivity, digestion of food
33
ethyl alcohol at 78ºC boiling point is a __ property
physical
34
hardness of a rock is a __ property
physical
35
sugar fermenting to form ethyl alcohol is a __ property
chemical
36
physical change
- change in 1 or more properties of a substance and not in its chemical composition
- ex: boiling pt or freezing water
- 3 states of water: in all phases, water mols are still intact; motion of mols and distance between them change
37
chemical change
- given substance becomes a new substance w/ diff properties and diff composition
- ex: Bunsen burner, methane reacts w/O2 to make CO2 and H2O, baking a cake, bleaching teeth (rxn happening), digesting food
38
crushing salt is a __ change
physical
39
burning wood is a __ change
chemical
40
dissolving sugar in water is a __ change
physical
41
melting a popsicle is a __ change
physical
42
element
a substance that CANNOT be broken down into other substances by chemical methods
- ex: Fe, Al, O2, H2
- all matter in world around us has elements
- almost 99% of mass of human body is made up of 6 elements (highest to lowest O2, C, H2, N, Ca, P)
43
compound
substance made of a given combination of elements that CAN be broken down into those elements by chemical methods
- ex: water, CO2, table sugar (C6H22O11)
- ALWAYS contains atoms of diff elements
- ALWAYS has the same composition/same combination of atoms
44
H2O, N2O4, NaOH, MnO2, and HF are ALL ___
compounds
45
pure substances
- always have same composition
- either elements or compounds
- ex: pure water (H2O), CO2, H2, gold (Au)
46
mixtures
- 2 or more pure substances
- have variable composition
- ex: wood, wine, coffee
- can be separated into pure substances that are elements and/or compounds
- 2 types: homogenous and heterogeneous
47
homogeneous mixture
- substance that is same throughout
- consists of visibly INDISTINGUISHABLE parts
- aka a SOLUTION
- doesn't vary in comp. from 1 region to another
- ex: air around us, brass, mashed potatoes, chocolate milk, table salt in water
48
heterogeneous mixtures
- consists of visibly DISTINGUISHABLE parts
- contains regions that have diff properties from other regions
- ex: oil and vinegar dressing, salad, sand in water, soup, chocolate chip cookies
49
organization of matter
MATTER
homogeneous mixtures heterogeneous mixtures
pure substances
elements
50
the elements
- 118 known
a) 88 occur naturally
b) rest have been made in labs
- vary in abundance
a) only 9 elements account for most of the compounds found in Earth's crust
b) these 9 elements account for over 98% of the total mass of the Earth's crust, oceans, and atmosphere
- list of elements found in living matter is very diff from those found in the Earth's crust
a) O2, N, and C forms the basis for all biologically important molecules
b) trace elements present in the body are very crucial
51
compound
district substance composed of atoms of 2 or more elements
| -always contains exactly the sam relative masses of those elements
52
chemical formulas
express types of atoms and # of each type in each unit, or molecule, of a given compound
53
rules for writing formulas
- each atom present is represented by its element symbol
- # of each type of atom is indicated by a subscript written to the right of the element symbol
- when only 1 atom of a given type is present, the subscript "1" is not written
54
what are atoms made up of?
e-, protons, and neutrons
55
electrons
e-; (-) charged; found outside nucleus
56
protons
(+) charged; found inside nucleus; has equal magnitude to e-
57
neutrons
no charge; found in nucleus; virtually same mass as proton
58
protons and neutrons have the same __
mass
59
mass charge of the e-, proton, and neutron
particle relative mass relative charge
e- 1 1-
proton 1836 1+
neutron 1839 none
60
why do diff atoms have diff chemical properties?
- the chemistry of an atom arises from its e-
- e- are part of atoms that intermingle when atoms combine to make molecules
- it's the # of e- that really determines chemical behavior
61
the chemistry of an atom arises from its __
electrons
62
isotopes
diff # of neutrons
- atoms w/ the same # of protons but diff # of neutrons
- show almost identical chem. properties
- chemistry of an atom is due to its e-
- in nature, elements are usually found as a mixture of isotopes
63
elements on periodic table are the most ABUNDANT __
isotopes
64
isotope symbol
```
A
X
Z
X= the chemical symbol of element
A= mass # (# of protons + # of neutrons)
Z= atomic # (# of protons)
```
65
the periodic table
shows all of the known elements in the order of increasing atomic #
66
groups/families
elements in same VERTICAL columns and have similar chemical properties
67
periods
HORIZONTAL rows of elements
68
metals
LEFT of staircase
| -most elements are these
69
non-metals
RIGHT of staircase
70
metalloids
ON the staircase
| -have some metallic and some non-metallic properties
71
what are the metalloids?
```
Boring Silly Germs Are Ants Telling Politics
Boron (B)
Silicon (Si)
Germanium (Ge)
Arsenic (As)
Antimony (Sb)
Tellurium (Te)
Polonium (Po)
```
72
** what are the four physical properties of metals? **
1) efficient conduction of heat and electricity
2) malleability (aluminum foil)
- they can be hammered into thin sheets
3) ductility
- they can be pulled into wires
- can be molded
4) lustrous appearance (shiny)
73
physical properties of non-metals
- lack properties of metals
- exhibit more variation in properties
- can be g, l, s @ room temp
74
physical properties of metalloids
exhibit a mixture of metallic and non-metallic properties
75
natural states of the elements
-most are reactive
-not generally found in pure form
-exceptions: noble metals ( gold, platinum, silver)
noble gasses: group 8
76
diatomic molecules
- so reactive they bind to themselves
- 7 diatomic molecules
- Nitrogen gas contains N2 molecules
- Oxygen gas contains O2 molecules
77
7 diatomic molecules
I Bring Clay For Our New Home
- Iodine (I2): lustrous, dark purple solid
- Bromine (Br2): reddish-brown liquid
- Chlorine (Cl2): pale green gas
- Fluorine (F2): pale yellow gas
- Oxygen (O2): pale blue gas
- Nitrogen (N2): colorless gas
- Hydrogen (H2): colorless gas
78
ions
- atom's not neutral
- atom w a charge
- elements become ions
- imbalance of e-
- atoms can form ions by gaining/losing e-
79
cations
metals tend to lose 1 or more e- to form (+) ions
80
anions
nonmetals tend to gain 1 or more e- to form (-) ions
| -name changes to end in -ide
81
ion charges & the periodic table
the ion that a particular atom will form can be predicted from the atom's position on the periodic table
82
ion charges and the periodic table chart
Group or Family Charge
Alkali Metals (1A) 1+
Alkaline Earth Metals (2A) 2+
Halogens (7A) 1-
Noble Gasses (8A) 0
```
*group 1: +1
group 2: +2
group 3: +3
group 6: -2
group 7: -1
group 8: 0
```
83
an ion with a 3+ charge w/ 24 e- is
Co3+
84
ion X+ has 54 e- and 78 neutrons. What is the mass number?
133
85
periodic table: Hydrogen
H
alkali metals
group 1
*diatomic
86
periodic table: Lithium
Li
alkali metals
+1
87
periodic table: Sodium
Na
alkali metals
+1
88
periodic table: Potassium
K
alkali metals
+1
89
periodic table: Rubidium
Rb
alkali metals
+1
90
periodic table: Cesium
Cs
alkali metals
+1
91
periodic table: Francium
Fr
alkali metals
+1
92
periodic table: Beryllium
Be
alkaline earth metals
+2
93
periodic table: Magnesium
Mg
alkaline earth metals
+2
94
periodic table: Calcium
Ca
alkaline earth metals
+2
95
periodic table: Strontium
Sr
alkaline earth metals
+2
96
periodic table: Barium
Ba
alkaline earth metals
+2
97
periodic table: Radium
Ra
alkaline earth metals
+2
98
periodic table: Scandium
Sc
| transition metal
99
periodic table: Yttrium
Y
| transitional metal
100
periodic table: Titanium
Ti
| transitional metal
101
periodic table: Zirconium
Zr
| transitional metal
102
periodic table: Hafnium
Hf
| transitional metal
103
periodic table: Rutherfordium
Rf
| transitional metal
104
periodic table: Vanadium
V
| transitional metal
105
periodic table: Niobium
Nb
| transitional metal
106
periodic table: Tantalum
Ta
| transitional metal
107
periodic table: Dubnium
Db
| transitional metal
108
periodic table: Chromium
Cr
| transitional metal
109
periodic table: Molybdenum
Mo
| transitional metal
110
periodic table: Tungsten
W
| transitional metal
111
periodic table: Seaborgium
Sg
| transitional metal
112
periodic table: Manganese
Mn
| transitional metal
113
periodic table: Technetium
Tc
| transitional metal
114
periodic table: Rhenium
Re
| transitional metal
115
periodic table: Bohrium
Bh
| transitional metal
116
periodic table: Iron
Fe
| transitional metal
117
periodic table: Ruthenium
Ru
| transitional metal
118
periodic table: Osmium
Os
| transitional metal
119
periodic table: Hassium
Hs
| transitional metal
120
periodic table: Cobalt
Co
| transitional metal
121
periodic table: Rhodium
Rh
| transitional metal
122
periodic table: Iridium
Ir
| transitional metal
123
periodic table: Meitnerium
Mt
| transitional metal
124
periodic table: Nickel
Ni
| transitional metal
125
periodic table: Palladium
Pd
| transitional metal
126
periodic table: Platinum
Pt
| transitional metal
127
periodic table: Copper
Cu
| transitional metal
128
periodic table: Silver
Ag
| transitional metal
129
periodic table: Gold
Au
| transitional metal
130
periodic table: Zinc
Zn
| transitional metal
131
periodic table: Cadmium
Cd
| transitional metal
132
periodic table: Mercury
Hg
| transitional metal
133
periodic table: Boron
B
+3
metalloid
134
periodic table: Aluminum
Al
+3
metal
135
periodic table: Gallium
Ga
+3
metal
136
periodic table: Indium
In
+3
metal
137
periodic table: Thallium
Tl
+3
metal
138
periodic table: Carbon
C
| nonmetal
139
periodic table: Silicon
Si
| metalloid
140
periodic table: Germanium
Ge
| metal
141
periodic table: Tin (stannum)
Sn
| metal
142
periodic table: Lead (Plumbum)
Pb
| metal
143
periodic table: Nitrogen
N
-3
non-metal
*diatomic
144
periodic table: Phosphorus
P
-3
nonmetal
145
periodic table: Arsenic
As
-3
metalloid
146
periodic table: Antimony
Sb
-3
metalloid
147
periodic table: Bismuth
Bi
-3
metal
148
periodic table: Oxygen
O
-2
nonmetal
*diatomic
149
periodic table: Sulfur
S
-2
nonmetal
150
periodic table: Selenium
Se
-2
nonmetal
151
periodic table: Tellurium
Te
-2
metalloid
152
periodic table: Polonium
Po
-2
metalloid
153
periodic table: Fluorine
F
-1
halogens
*diatomic
154
periodic table: Chlorine
Cl
-1
halogens
*diatomic
155
periodic table: Bromine
Br
-1
halogens
*diatomic
156
periodic table: Iodine
```
I
group 7
-1
halogens
*diatomic
```
157
periodic table: Astatine
At
-1
halogens
158
periodic table: Helium
He
0
noble gases
159
periodic table: Neon
Ne
0
noble gases
160
periodic table: Argon
Ar
0
noble gases
161
periodic table: Krypton
Kr
0
noble gases
162
periodic table: Xenon
Xe
0
noble gases
163
periodic table: Radon
Rn
0
noble gases
164
Which of the steps in the scientific method is missing from the following situation?
“Your instructor is holding a balloon and quickly inhales some of the gas inside the balloon. He then speaks and his voice changes to a high-pitched sound (and sounds quite funny!). He then asks you to determine what gas was inside the balloon that he inhaled. Based on your observations, you conclude that the gas must be helium.”
perform experiments
165
what is chemistry?
The science that deals with the materials of the universe and the changes that these materials undergo.
- The central science
- Understanding most other fields of science requires an understanding of chemistry.
166
solving problems w/ a scientific approach
1.Recognize the problem and state it clearly.
a)Making an observation.
2.Propose possible solutions to the problem or possible explanations for the observation.
a)Formulating a hypothesis.
3.Decide which of the solutions is the best or decide whether the explanation proposed is reasonable
.a)Performing an experiment.
167
science
a framework for gaining and organizing knowledge.
•a plan of action —a procedure for processing and understanding certain types of information.
•Scientists are always challenging our current beliefs about science, asking questions, and experimenting to gain new knowledge.
-Scientific method is needed.
168
Which of the following correctly expresses 7,882 in scientific notation?
7.882 × 10^3
169
Which of the following correctly expresses 0.0000496 in scientific notation?
4.96 × 10^–5
170
Choose the statement(s) that contain improper use(s) of commonly used units
A basketball is 7 m tall
| A nickel is 6.5 cm thick
171
What data would you need to estimate the money you would spend on gasoline to drive your car from New York to Los Angeles? Provide estimates of values and a sample calculation.
Distance between New York and Los Angeles is 2500 miles
– Average gas mileage is 25 miles per gallon
– Average cost of gasoline is $3.25 per gallon
2500 mi x 1 gal/25 mi x $3.25/1 gal = $325
172
The normal body temperature for a dog is approximately 102°F. What is this equivalent to on the Kelvin temperature scale?
312 K
173
A certain mineral has a mass of 17.8 g and a volume of 2.35 cm^3. What is the density of this mineral?
7.57 g/cm^3
174
What is the mass of a 49.6 mL-sample of a liquid, which has a density of 0.85 g/mL?
42 g
175
If an object has a mass of 243.8 g and occupies a volume of 0.125 L, what will be the density of this object in g/cm^3?
1.95 g/cm^3
176
Copper has a density of 8.96 g/cm^3. 75.0 g of copper is added to 50.0 mL of water in a graduated cylinder. Determine the volume reading to which the water level in the cylinder will rise.
58.4 mL
177
Which of the following are examples of a chemical change?
Burning of wood
178
Which of the following is a homogeneous mixture?
gasoline
179
A certain isotope X contains 23 protons and 28 neutrons
•What is the mass number of this isotope?
•Identify the element
Mass Number = 51
| Vanadium
180
compounds that contain ions: ionic compounds
- ions combine to form ionic compounds
- properties of ionic compounds:
1. high melting pts
2. conduct e-
- if melted
- if dissolved in water
- transfer e-
- strongest bonds
- bond between a metal and a nonmetal
- electrically neutral
- charges on anions and cations in compound must = 0
181
compounds that contain ions: formulas for ionic compounds
- write cation element symbol followed by anion element symbol
- # of cations and anions must be correct for their charges to = 0
- if they don't = 0, u must balance them
ex: MgCl2 = Mg (2+) and 2( Cl(-1) ) -> Cl (-2) = compound net charge of 0 for MgCl2
182
name the ionic compound NaBr
sodium bromide
183
name the ionic compound calcium fluoride
CaF2
184
name the ionic compound KCl
potassium chloride
185
name the ionic compound lithium iodide
LiI
186
name the ionic compound MgO2
magnesium oxide
187
e- give __; protons and neutrons give __
size; weight
188
out of all 3, which is the smallest subatomic particle?
e-
189
what are the 3 steps of the scientific method?
1) make an observation
2) form a hypothesis
3) perform experiment
-leads u to
theory: answers "why?", leads to more questions
the law: "this is what happened", doesn't lead to more questions
190
sig fig question: 1.5 +3.000 - 4
4.5- 4 = 0.5 = 5 x 10^-1
191
1 kg = __ g
1000
192
1000 mL= ___ L
1
193
100 cm= __ m
1
194
1000 mg= __ g
1
195
1 mL= __ cm^3
1
196
100 mm= __ m
1
197
1 lb= __ g
453.59
198
1 kg= _ Ibs
2.2046
199
1 in = __ cm
2.54
200
periodic table: darmstadtium
Ds
| transition metal
201
periodic table: roentgenium
Rg
| transition metal
202
group 1
| +1
```
alkali metals
Highly Nasty Kids Rub Cats
Li (lithium)
Na (sodium)
K (potassium)
Rb (rubidium)
Cs (cesium)
```
203
group 2
| +2
```
alkaline earth metals
Beer Mugs Can Serve Bar Rats
beryllium (Be)
magnesium (Mg)
calcium (Ca)
strontium (Sr)
barium (Ba)
radium (Ra)
```
204
group 3
| +3
```
Bears Always Give In
boron (B)
aluminum (Al)
gallium (Ga)
indium (In)
```
205
group 6
| -2
```
Old Soldiers Seem Tense
oxygen (O)
sulfur (S)
seaborgium (Se)
tellurium (Te)
```
206
group 7
| -1
```
halogens
“Floor Cleaner Broken?” I Asked
fluorine (F)
chlorine (Cl)
bromine (Br)
iodine (I)
```
