صفحه 1:
General Chemistry
M. R. Naimi-Jamal
Faculty of Chemistry
Iran University of Science & Technology
صفحه 2:
صفحه 3:
ارزشیابی
غیبت مجاز: ۳/۱۷ کل ساعت درسی
صفحه 4:
:فصل اول
صفحه 5:
[EMISTRY:
emistry is the study of the properties, compos
d structure of matter, the physical and chemic
anges it undergoes, and the energy liberated c
sorbed during those changes.
مم | ۱۳
صفحه 6:
Why Study Chemistry?
1. To better understand the world: what it is
made of and how it works.
2. Because it is the most practical and
relevant of the sciences - chemistry is the
study of EVERYTHING!
3. It is the “Central Science” - All other
sciences intersect at and depend on
chemistry.
4. It is essential to the national and local
economies.
5. It is required for virtually every major
involving Science mathematics oar
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Chemistry is an Observational
Science
>» Observation: Using the five senses to “see” what
is and happens around you.
>» Conclusion: An explanation of the cause or causes
for one or more observations.
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Observations vs. Conclusions
OBSERVATION:
* When electricity is passed through a salt
solution, a yellow-green gas and a colorless,
flammable gas forms.
CONCLUSION:
¢ The yellow-green gas is chlorine and the
colorless gas is hydrogen.
صفحه 9:
1. Collect Facts or Data (Observe!!)
2. Search for Generalizations or Laws to Summarize
the Facts.
3. Freely Use Your Imagination to Construct Theories
or Models of Nature that Will Account for the Laws.
4. Test Theories/Hypotheses for Accuracy.
5. Modify Theories/Hypotheses as Necessary Based
on Your Test Results.
صفحه 10:
ماده و انرژی
واحد های بین المللی SI
عدم قطعیت و ارقام معنی دار
آنالين ابعادى
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ماده (Matter) :20 فضا اشغال مى كندء جرم واينرسى دارد
انرذى 1513816[9) توانايى انجام كار يا توليد حرارت
صفحه 13:
رابطه اینشتین
E=me
جرم - انرژی
صفحه 14:
The Law of Conservation of Matter:
Matter is neither created nor destroyed
during a chemical reaction or a physical
change.
The Law of Conservation of Energy:
Energy is neither created nor destroyed
during a chemical reaction or a physical
change. It can only be changed from one
form into another.
The Law of Conservation of Matter/Energy:
The combined amdint of matter and energy
in the universe is cmrstant.
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Solid: has a rigid shape and a fixed volume that
changes very little with temperature and pressure
Liquid: like solids have a fixed volume but no
definite shape (take on the shape of the
container)
Gas: no fixed volume - volume determined by the
size of the container - the volume of a gas varies
greatly with temperature and pressure
صفحه 17:
0
(leteroqeurvus|
wixtures
مساوم
لد ووه
ات
امن
سس
Gewrute
صفحه 18:
* Substance (16 o) A distinct type of
matter. All samples of a substance have
the same properties. Elements and
compounds are substances.
* Mixture J.) A sample of matter
consisting of two or more substances
which are NOTchemically combined.
صفحه 19:
Classification of Matter (Substa:
Substances:
٠ Element: A substance that cannot be broken down
(decomposed) into simpler substances by chemical
reactions, e.g.: iron, gold, oxygen.
es)
* Compound: A substance composed of two or more
elements chemically combined in fixed ratios by mass.
Water - H,O Carbon dioxide - CO,
Sodium chloride - NaCl Iron(II) sulfide - FeS
صفحه 20:
Classification of Matter (Mixtures)
Mixtures:
* Homogeneous: A mixture having only
one phase; it is uniform (the same)
throughout and has the same properties
throughout. These are called ,, Solutions”.
‘ Heterogeneous: A mixture with more
than one phase. It is non-uniform and does
NOT have the same properties throughout.
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° Phase - A sample of matter that is
uniform in composition and physical
state and is separated from other
phases by a definite boundary.
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° Physical Change:
A change in which each substance
involved in the change retains its
original identity and no new
elements or compounds are formed.
Hos) HF ممم
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* Chemical Change:
A change in which one or more
elements or compounds
(substances) are formed.
2H, (g) + 0. 2
13,0 ۵
AgNO,(aq) + HCl(aq) > AgCl(s) + HNO,(aq)
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® Okewird ged physicdl chore
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صفحه 26:
کروماتو گررافی
(Chromatography)
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صفحه 28:
Measurement
٠ Chemistry is an Observational science.
* Chemistry is a Quantitative science.
° Measurement - A quantitative
observation.
صفحه 29:
Measurement
All measurements have three parts:
1. A value
2. Uni 26.9762 g
3. An Unce ity
Examples: 33.2 mL 72.36 mm
426 kg 31 people
صفحه 30:
Measurement
Conversion Factors: A fraction
whose numerator and
denominator contain the same
quantity expressed in different
1 علنص 1 ع 20و باه _ 5280 ft. q
5280 ft 1 mile
1 همس 0.01 د هه icm__9.01m_ 4
0.0im icm
2-54cm__1lin — مين 2.54 د ص11
1in 2.54 cm
صفحه 31:
Measurement
Uncertainty in Measurements:
Exact Measurements:
Measured values determined by counting
or when a value is defined.
Examples: 31 people, 27 rocks, 2.54
cm = lin
The uncertainty in these measurements =
0
Non-exact Measurements:
All other measurements. The last digit
recorded is uncertain; it is estimated!!
Examples: 27.5g, 32.7mm 12 467
km
صفحه 32:
Measurement
Significant Figures: اریقام
معنیار
Each digit obtained as a result of a
measurement includes all of the
certain digits and the first uncertain
digit. The number of significant
figures in a measurement is an
indicator of the sensitivity of the
measurement.
صفحه 33:
Measurement
Rules for Significant Figures:
‘ All non-zero digits are significant.
25.79 km 27 mL
/ A zero between other significant figures is
significant.
207.9 nm 100.7 mL
صفحه 34:
Measurement
v Initial zeros are NOT significant:
J 0.001 23 cm?
v Final zeros after the decimal point ARE
significant:
23.100 ps
v Final zeros in a measurement with no
decimal point may
or may not be significant.
3200 cm (might have 2,
3, ord
significant figures!!)
v Exact measurements have an infinite
number of
صفحه 35:
Measurement
Count from left from first non-zero
digit.
Significant
Figures
3 3
2
2
infini
bad
notation
Number
6.29 g
0.00348 g
9.0
1.0 x 10%
100 eggs
100 g
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(Rounding Off) ردن 5 ۹
Report to 3 significant figures:
10.235 > 10.
12.4790 > 2
19.75 > 12.
15.639 2 5
7.025 > 19.
Note: 3rd digit is increas@d.by one if
Ath digit >5 and decyeased to
zero if 4th digit <5.
If 4th digit is =5, 3rd/dWjit is
increased only if it is!an odd
number!
صفحه 37:
لت محاسبات رياضى
iding and subtracting:
se the number of decimal places in the number with |
west decimal places.
11.676
+ 1.14
+ 0.6
13.416 ۵4
35.2 mL + 0.34 mL = 3854 mL = 35.5 mL
1.00794 ۲ + 1.490 ۰ + 15.9992/4 <- 4
u= 18.497 u
صفحه 38:
لت محاسبات رياضى
Multiplying and dividing:
Use the fewest significant figures.
4 3
0.01208 + 0.236
= 0.51186
= 5.12 x
107
(9.5760 g)/(12.2 mL) =
0.285 g/mL 5
صفحه 39:
cre slowly ال
جرم کیلوگرم Kg
طول متر m
زمان al 5
جریان dy آمپر A
دما کلوین K
شدت درخشش شمع ed.
مقدار ماده مول mol
صفحه 40:
Derived Quantities
Force Newton N=kgm
s2
Pressure Pascal Pa=kgm
1g2
Eenergy Joule [ - تس وكا
Common Units عطقي
Length Angstrom A=10%cm
Volume Litre L= 103 m3
Energy Calorie cal = 4.184 J
Pressure Atmosphere 1 atm = 1.064x
10? kPa
= 760 mm Hg
صفحه 41:
EIB
دكا
دسى
سانتى
ميكرو
ELBE
8
| | ۵ ایب
رد استفاده 195
10°
103
10
107
102
103
106
105
10
1
1 1۷8 - 1106
1 16 - 1103
1 dm = 1x10'm
صفحه 42:
Properties of Matter
* Extensive Properties (cjbiawols):
Properties that depend on the amount of matter
present in a sample.
Mass Volume Heat Capacity
* Intensive Properties ( jsitwols):
Properties that do NOT depend on the amount
of matter present in a sample.
Color Temperature Density
Melting Point Specific Heat Boiling Point
صفحه 43:
Temperature an ermal Energy
Temperature: A measure of _ the
“hotness”and “coldness” of an object; a
measure of the average kinetic energy of
the atoms and molecules of the object.
The higher the temperature, the more
kinetic energy the atoms and/or molecules
Wavemal Energy: Often called “heat”, it is
the form of energy toward which all other
forms tend to go.
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emperature) |,
@ 0
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2۴ 0 Weter boils
0
&
g
98,6۴ 8 Normal body temperature
8
327۴ ۲ Water freezes
Fahrenheit scale
I 100°C 4
— z
8 8
3 37.00 3
8 8
۱ wet
Kelvin scale Celsius scalo
973 K
310K
273K
صفحه 46:
این مقیاس به افتخار گایربل دانبل فارنهایت که دماسنج جیوهای را اختراع کرد
نامگذاری شدهاست. براساس مقالهای که در ۱۷۲۶ توسط او نوشته شده.
مقیاس او براساس سه نقطه پلیه گذاری شدهاست. نقطه اول دمای مخلوط یک
به یک لب ویخ و نشادر است که به عنوان صفر در نظر گرفته شدهاست. نقطه
بعدی دمای مخلوط یک یه یک لب خللص و یخ است و نقطه سوم دمای بدن
انسان. فارنهلیت بعد از مشاهده فاصله لین نقاط از هم به لين نتيجه رسيد كه
فاصله نقطه ذوب یخ خللص و یخ با نشادر نصف فاصله نقطه ذوب یخ خالص از
دمای بدن است. پس برای سادگی تقسیم بندی بین این نقاط فاصلهها را به دو
مقدار ۳۲ قسمتی و ۶۴ قسمتی تقسیم نمود که با نصف کردن چند باره
فاصلهها امکان پذیر است. پس در مقیاس او دمای ذوب یخ خالص برابر با ۳۲ و
دمای بدن برابر با ۹۶ درجه(۳۲+۶۴) اندازه گیری شد. فارنهایت مشاهده کرد
که آب با
مقیاس تغییراتی دادند تا نقطه ذوب یخ دقیقا ۳۲ درجه و دمای جوش آن
۲ درجه در نظر گرفته شود و فاصله آنها ۱۸۰ واحد باشد. به خاطر همین
تغییرات دمای بدن انسان در این مدل حدود VA درجه به دست آمد.
مقیاس در ۲۱۲ درجه به جوش میآید. بعدها دانشمندان در این
صفحه 47:
تبديل واحدهاى دما
کلوین به سانتی گراد: 5 +0 از
فارنهایت به سانتی گراد: 0 ۳-32 ۲
0 180
Note: K andnot °K
صفحه 48:
ample Caiculations involving
Titty! 0
Example:
Convert 73.6 °F to Celsius and Kelvin temperatures.
°C = (5/9) (CF - 32) K=°C + 273.15
NG
(5/9)(73.6 °F - 32)
)5/9( 4 18(1
K
23.1°C + 273.15
296.3 K
صفحه 49:
3
باه 107-۱ مج
صفحه 50:
Stopcock,
avalve to
control the
liquid flow
Buret
Pipet Volumetric flask
Graduated cylinder
صفحه 51:
Dimensional Analysis
ow many meters are in each of the following?
21 km 1023570 um
(21 km)QL x 103m) < 21 ۶ 10321 x 104m
(1023570 pany ( im __ 3.023570 m
(10° ud
صفحه 52:
Sample Calculations Involving Volumes
How many mL are in 3.456 L?
mL. 3456 mL هت
How many uL are in 23.7 cm?
foe mS بل 1 )101 ل )
at m*) (10
x 104 pL 2.37 ۱۶ م0( ک
صفحه 53:
Dimensional Analysis
How many mL are in 3.0 ft’?
1 ft = 12 in1 in = 2.54 cni cm’ = 1 mL
( )12 1(( (ص12) )22 in\(2.54 ecm) (2.54 cm) (254 cm) (1
)1 ۶( 01۶۵ CNt) \1 in) (Nn) \ (Nn)
= 8.5 x 10* mL
How many ns are in 23.8 s?
(23.8 Dag ape x 10°ns = 2.38 ۶ 1010 8
صفحه 54:
1۷۲۵95 2: ۷۲
ass: the measure of the quantity or amount of
atter in an object. The mass of an object does
ange as its position changes.
Mass is measured using a BALANCE.
ight: A measure of the gravitational attractio:
earth for an object. The weight of an object
nges with its distance from the center of the «
Weight is measured using SCALES.
صفحه 55:
Sample Calculations Involving Masses
¢ How many yg are in 2.56 kg?
39 sO CED 2-56 x 10° pg
* How many g are in 2.578 x 10" ng?
: 1
(2.578 x تا ۲ a 2578 g
صفحه 56:
(9
04 - ۷
unit: commonly g/mL
m = Vd V = m/d
Mass and volume are extensive
properties
Density is an intensive property
صفحه 57:
What is the density of a cubic block
of wood that is 2.4 cm on each side
and has a mass of 9.57 g?
volume = [2.4 cm x 2.4 cm x 2.4 cm]= 13.8 cm?
density = (9.57 g)/(13.8 cm?)
= 0.69 g/cm’ = 0.69 g/mL
Note again: 1 cm? = 1 mL
صفحه 58:
What is the mass of a cube of osmium
that is 1.25 inches on each side?
Density is 22.48g/cm3
(converts in. toem) (converts cm to cm3) (converts cm? to g osmium)
= 719 g osmium
1
نجوه و 48 22 2
osmium ع 2248 پر osmium 2 all ع 7
len?
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صفحه 60:
۱092۰۱۵2۱۰۸۸۹ 8 pic
۰ Systematic errors
- Thermometer constantly 2°C too low.
° Random errors
- Limitation in reading a scale.
° Precision
- Reproducibility of a measurement.
«
- How close to the real value.
صفحه 61:
=i
صحت و دقت در اندازه گیر
ا صحت به معنای
درستى و به دست
آوردن مقدار واقعى
در یک اندازه گیری
لا دقت به معنای نزدیک
بودن مقدارها در چند
بار اندازه گیری
لا دقت خوب
Sees i
الا دقت خوب
الا صحت بد
لا دقت بد
صفحه 62:
Chapter 1, Questions
3,5, 12, 14, 17,
30, 38, 43, 49,
59, 60