普通化學甲
蔡蘊明
1
Chemists and Chemistry
化學是研究物質的組成、製備、性質
及其應用的科學。
Chemistry is the study of the
compositions, preparations, properties
of substances and its applications.
1
※ Introduction
Life
生老病死
Medicinal
Living
食衣住行
Chemistry
A center of science
Chemicals
Food
Environmental
Materials
A science of problem solving
Literature search: understand the structure
the reaction
Identify the mechanism: source of the problem
Propose some solutions
Experiments
2
Scientific method
1. Observation
Qualitative
Quantitative
2. Hypothesis
3. Prediction
4. Tested by experiments  new observation
Theory – explain what happens
(theory may change)
Law –
summarizes what happens
◎ Industrial chemistry
Isolation of natural product as raw material
Process raw material  commercial product
The use of chemicals
Economy and safety are critical
Research in industrial chemistry
1. Identify a need
2. Develop a process
3. Evaluation: efficiency, cost, ease of production,
safety, environmental impact
4. Pilot plant
↓
Real production
3
※ Units of measurement
Prefix
Symbol
Exponential Notation
giga
G
109
mega
M
106
kilo
k
103
hecto
h
102
deka
da
101
deci
d
10-1
centi
c
10-2
mili
m
10-3
micro

10-6
nano
n
10-9
pico
p
10-12
femto
f
10-15
atto
a
10-18
Volume 91
Issue 33,
pp. 10-13
Issue Date:
August 19,
2013
4
SI system
SI system
1068
1064
1060
1056
1052
1048
1044
1040
1036
1032
1028
1024
1020
1018
1016
1015
1012
109
108
106
104
103
102
101
0
無量大數 無量數
不可思議
那由他
阿僧祇 阿僧秪
恒河沙
極
載
正
澗
溝
穰
杼秭
垓
exa(E)
京
peta(P)
tera(T)
兆
giga(G)
億
mega(M)
万
kilo(k)
千
hecto (h)
百
deka(da)
十
零
10-1
10-2
10-3
10-4
10-5
10-6
10-7
10-8
10-9
10-10
10-11
10-12
10-13
10-14
10-15
10-16
10-17
10-18
10-19
10-20
10-21
分
厘
毛 豪
糸
忽
微
織 纖
沙
塵
埃
渺
漠
模糊
逡巡
須臾
瞬息
彈指
剎那
六德
虛空
清淨
deci(d)
centi(c)
milli(m)
micro(u)
nano(n)
pico(P)
femto(f)
atto(a)
清朝「數理精蘊」
5
一
元
硬
幣
人
之
身
高
10 3m
1m
10-2m 10 -3m
(Km)
公尺
公里
分子
～1 nm
紙頭
張髮
之之
厚粗
度細
公里
公分
︵
積次
體微
電米
路︶
奈
米
科
技
分
子
10-9m 10 -10m
10-6m
(mm)
(μm)
(nm)
。
(A)
毫米
微米
奈米
埃
分子官能基化
成具實用之材料
原
子
核
原
子
10-12m
奈米材料
工業上之製程改進
1～10 nm
10-15m
(pm)
(fm)
公里
皮米
飛米
公里
次微米
100 nm
0.1 μm
※ Uncertainty in measurement
A measurement always has some degrees of uncertainty
20
20.1
certain digits
20.13
21
uncertain digit
(estimated)
Take only one uncertain digit
6
An IR spectrum of cyclohexanone
※ Precision and accuracy
Precision (精確度): The degree of
agreement among several measurements.
x
x
x
x
x
low
precision
x
x xx x
x
high
precision
x
The error is called random error or indeterminate errors
(非定向的)
7
Accuracy (準確度): Agreement with the true value
high precision
but low accuracy
xx
xx x
x
The error is called systematic error or determinate error
Ex.
Weighting
Result
1
2.486
2
2.487
3
2.485
4
2.484
5
2.488
Avg: 2.486
Without systematic error, this
value is the closest to the true
value.
May be recorded as 2.486 ± 0.002
8
※ Significant figures and calculations
Significant figures (digits)
Rules
1. Nonzero integers: always count
2. Zeros
a. Leading zeros: preceding all the nonzero digits
─ does not count.
0.0025
b. Captive zeros - count
1.008
c. Trailing zeros
2500
do not count
25.00
count
3
2.500 x 10 = 2500.
count
9
3. Exact numbers
Not obtained using measuring devices
Arise from definition
Infinite number of digits
Ex. 2 r
Exact number
8 apples
1 in = 2.54 cm
Definition
Mathematical operations
1.
×, ÷
Same as the least precise measurement
4.56 × 1.4 = 6.384
corrected
6.4
==
two
==
two
四捨五入
10
2.
+ ,
12.11
18.0
1.013
31.123
corrected
31.1
11