9/23/11
The Periodic Table of the Elements
1
18
1
H
2
2
1.0079
3
Li
13
4
5
Be
B
6.941 9.01218
11
12
Na Mg
22.9898
19
K
39.0983
37
Rb
85.4578
55
Cs
3
24.305
20
Ca
4
21
Sc
Ra
Y
24
V
Zr
8
25
Cr
Hf
178.49 180.948
104
105
27
Fe
Tc
W
10
Co
55.847 58.9332
44
45
Ru
95.94 98.9063
74
75
Ta
9
26
Mn
Nb Mo
91.224 92.9064
72
73
La
Re
183.85 186.207
106
107
Rh
28
Ni
58.69
46
Pd
11
29
Cu
63.546
47
Ag
12
30
Zn
65.39
48
Cd
15
6
C
16
7
N
Si
P
26.9815 28.0855 30.9738
31
32
33
Ga
69.723
49
Ge
As
72.61 74.9216
50
51
In
Sn
Sb
114.82
81
118.71
82
121.75
83
Pt
Tl
Pb
Bi
192.22
109
195.08 196.967
4.0026
10
Ne
12.011 14.0067 15.9994 18.9984 20.1797
14
15
16
17
18
106.42 107.868 112.411
78
79
80
190.2
108
9
F
Al
Os
Au Hg
8
O
10.811
13
101.07 102.906
76
77
Ir
He
17
200.59 204.383
207.2
S
Cl
Ar
32.066 35.4527
34
35
39.948
36
Se
Kr
78.96
52
Te
Br
79.904
53
I
127.6 126.905
84
85
Po
83.8
54
Xe
At
131.29
86
Rn
208.98 208.982 209.987 222.018
Ac Unq Unp Unh Uns Uno Une
223.02 226.025 227.028 -
58
Lanthanides
Actinides
7
47.88 50.9415 51.9961 54.9381
40
41
42
43
132.905 137.327 138.906
87
88
89
Fr
6
23
Ti
87.62 88.9059
56
57
Ba
5
22
40.078 44.9559
38
39
Sr
14
59
60
61
62
63
64
65
Ce
Pr
Nd Pm Sm Eu
Gd
Tb
140.12
90
140.91
91
144.24
92
157.25
96
158.92
97
Th
232.038
Pa
231.04
U
238.03
146.92
93
150.35
94
151.96
95
66
67
Dy Ho
162.5
98
71
Lu
174.97
103
Fm Md No
Pu Am Cm Bk
Cf
Es
239.05
251.08
254.09
249.08
70
168.93
101
237.05
247.07
69
Tm Yb
167.26
100
Np
241.06
68
Er
164.93
99
257.1
258.1
Chem 6A Michael J. Sailor, UC San Diego
173.04
102
255
Lr
262.1
1
The Periodic Table of the Elements QUIZ
THURSDAY Oct 20
Chem 6A Michael J. Sailor, UC San Diego
2
1
9/23/11
The Periodic Table of the Elements QUIZ
Thurs Oct 20
Provide the names of the following elements:
Mg
Br
Na
Fe
Pt
Se
Sb
Etc…
Chem 6A Michael J. Sailor, UC San Diego
3
Prefixes-Memorize
Prefix
Mega
Kilo
Deci
Centi
Milli
Micro
Nano
Pico
Name
M
k
d
c
m
µ
n
p
Number
106
103
10-1
10-2
10-3
10-6
10-9
10-12
Chem 6A Michael J. Sailor, UC San Diego
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9/23/11
Units
Science uses METRIC (or SI) units, not
ENGLISH Quantity Common SI Unit Mass
1 pound 453.6 grams (g) Length 1 inch
2.54 centimeters (cm)
Volume 1 quart 0.946 liters (L) Chem 6A Michael J. Sailor, UC San Diego
5
Temperature
Process
Water Boils
Water Freezes
Absolute Zero
Fahrenheit (°F)
212
32
-459.67
Celsius (°C)
Kelvin (K)
100
0
-273.15
373.15
273.15
0 CONVERSIONS:
Degrees F = 1.8 x Celsius + 32
Kelvin = Celsius + 273.15
Chem 6A Michael J. Sailor, UC San Diego
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3
9/23/11
Problem: Derived units
The density of gasoline is 0.78 g/
mL. What is the mass (in kg) of 1
gallon of gasoline? There are 3.79
liters in one gallon. Set up the
problem without solving it.
Chem 6A Michael J. Sailor, UC San Diego
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Solution:
Mass =
1 gallon 3.79 L
1gallon
1000 mL
1L
0.78 g
mL
Chem 6A Michael J. Sailor, UC San Diego
kg
1000 g
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4
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Significant figures
Rules: 1.  Nonzero digits are always significant
5.345 has 4 sig. figs
Chem 6A Michael J. Sailor, UC San Diego
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Significant figures
Rules: 2. Zeros: a.  leading zeros do not count - 0.0025 has 2
sig.fig.
b.  zeros in between ("captive zeros") do
count - 0.2005 has 4 sig.fig.
c.  trailing zeros count only if the number
contains a decimal point
Chem 6A Michael J. Sailor, UC San Diego
10
5
9/23/11
Significant figures
trailing zeros count only if the number
contains a decimal point
examples:
100 1.00 x 102
100.
has 1 sig. fig.
has 3 sig.figs
has 3 sig.figs
Chem 6A Michael J. Sailor, UC San Diego
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Significant figures
Rules: 3. Exact numbers count as infinite # of sig.fig.
example:
Say we make 4 measurements of the mass of a
cigar and we get: 125 g, 126 g, 127 g, and 128
g. What is the average?
Chem 6A Michael J. Sailor, UC San Diego
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9/23/11
Significant figures
Answer: Average = (125 + 126 + 127 + 128)/4 = 126.5 g
There are only 3 sig.figs in the numbers and 4
(the number of measurements) is an "exact"
number. It does not limit the number of sig.figs,
so the mass of the cigar we should report is =
126
Why not 127? Chem 6A Michael J. Sailor, UC San Diego
13
Rounding
In this course, if you have to eliminate “5”
in a rounding operation, always round so
that the final answer is even: 126.5 rounds (down) to 126
127.5 rounds (up) to 128
What about 126.52?
This number is closer to 127 than it is to 126,
so it rounds up to 127.
Chem 6A Michael J. Sailor, UC San Diego
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Problem: arithmetic with significant figures
Four samples are weighed, giving values of
2.397, 951, 0.001173, and 112.55 grams,
respectively. What is the number of significant
digits that should be used when reporting the
total mass?
a) 1
b) 2
c) 3
d) 4
e) none of the above
Chem 6A Michael J. Sailor, UC San Diego
15
Solution:
2.397
951
0.001173
112.55
1065.948173
= 1066 g (4 significant digits)
(if multiplied, the answer is = 300.948416 = 301,
only 3 significant digits)
Chem 6A Michael J. Sailor, UC San Diego
16
8
9/23/11
Problem: dimensional analysis
The biological warfare agent Botulinum toxin has a
molecular weight of 150,000 g/mol. It takes
approximately 0.1 µg of the toxin to kill an average
person. How many grams would be needed to kill
300 million people?
a) 15,000 kg, enough to fit in a tank car
b) 1500 g, enough to fit in a suitcase
c) 300 g, enough to fit in a soda can
d) 30 g, enough to fit in an aspirin bottle
e) none of the above
Chem 6A Michael J. Sailor, UC San Diego
17
Problem: dimensional analysis
The biological warfare agent Botulinum toxin has a
molecular weight of 150,000 g/mol. It takes
approximately 0.1 µg of the toxin to kill an average
person. How many grams would be needed to kill
300 million people?
0.1µg 300x10 6 persons
1g
×
× 6
= 30g
person
10 µg
Answer: (d)
€
Chem 6A Michael J. Sailor, UC San Diego
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Accuracy and Precision
ACCURACY = how close a measured value is to
the true value. PRECISION = how close you come to a given
value on each measurement (i.e. reproducibility). Chem 6A Michael J. Sailor, UC San Diego
19
Errors in Measurements
Random (indeterminate) – noise, like tossing a coin. Systematic (determinate) - something you can figure out. Example: using a tennis ball launcher pointed at the wrong
spot. If the ball launcher consistently hits a spot out of
bounds, you would say that the instrument is precise
(because it hits the same spot every time) but it is not very
accurate (it doesn't land in the service court) and that it
shows a systematic error (it lands out of bounds but you
can adjust the ball launching system so that it delivers the
serve in bounds).
Chem 6A Michael J. Sailor, UC San Diego
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10