Chemistry

2. Chapter-1: The Study of Change
(Quiz-1)
1.1: Chemistry: A Science for the Twenty-First Century
1.2: The Study of Chemistry
1.3: The Scientific Method
1.4: Classifications of Matter
1.5: The Three States of Matter
1.6: Physical and Chemical Properties of Matter
1.7 : Measurement
1.8: The Importance of Units
1.9: Handling Numbers
1.10: Dimensional Analysis in Solving Problems

3. Chapter-1: The Study of Change
(Quiz-1)
1.1: Chemistry: A Science for the Twenty-First Century
1.2: The Study of Chemistry
1.3: The Scientific Method
1.4: Classifications of Matter
1.5: The Three States of Matter
1.6: Physical and Chemical Properties of Matter
1.7 : Measurement
1.8: The Importance of Units
1.9: Handling Numbers
1.10: Dimensional Analysis in Solving Problems

4. 1.1. Chemistry: A Science for the Twenty-First
Century
• Ten Chemical Innovations That Will Change
Our World: IUPAC
(The International Union of Pure and Applied Chemistry)

5. Some Land Mark Discoveries in Chemical
Sciences
• 1. Oxygen (1770s)
2. Atomic Theory (1808)
3. Atoms Combine Into Molecules (1811 onward)
4. Synthesis of Urea (1828)
5. Chemical Structure (1850s)
6. Periodic Table of the Elements (1860s - 1870s)
7. Electricity Transforms Chemicals (1807 - 1810)
8. The Electron (1897)
9. Electrons for Chemical Bonds (1913 onward)
10. Atoms Have Signatures of Light (1850s)
11. Radioactivity (1890s - 1900s)
12. Plastics (1869 and 1900s)
13. Fullerenes (1985)

7. 1. Transparent Wood (01.21) University of Maryland, Baltimore USA.
Lignin + H2O2
UV light (or natural sunlightunlight
White Colour
1. Soaked in ethanol
2.The pores are filled with colourless epoxy
perfectly transparent
wood

8. 2. Ink for digital printing on
porcelain (03.21)
• Italian company Metco
• The digital colouring of ceramic tiles, which may
replace the classic glazing method, is to become a
breakthrough for this industry.
• Called ECO-INK for digital ceramics- An
innovative, sustainable ink for printing digital
porcelain

9. 3. Magnetic Polymers (03.21)

10. 4. Newly discovered effects of a natural medicine with
one thousand years of history (04.21) University of Warwick,
• An ‘antibiotic’ vegetable paste whose recipe is 1,000
years old. It is called ‘vision repairing ointment’.
• The ointment, which contains onions, garlic, cow bile
and wine, has extremely potent antiseptic properties.
• [Cattle bile (CB) has long been used in Japan as an
ingredient of digestive medicines]. Experiments have
shown that this natural medicine can be a powerful
weapon against bacteria called biofilms. This is one of
the most dangerous types of bacteria. This recipe is
Applicable for diabetics,

11. 5. Vanilla Flavouring Based on Plastic (06.21)-
Plastic Bottle
(Polyethylene
Terephthalate)
Genetically modified E. coli bacteria
Vanillin
Terephthalic Acid
(TA),
University of Edinburgh

12. 6. Plastic-eating Yeasts to Save the Planet (09.2021)-
Dr Piotr Biniarz from the Wrocław University of Environmental
and Life Sciences
Plastic Bottle
(Polyethylene
Terephthalate
-PET )
(a mutant enzyme)
Ideonella Sakaiensis 201-F6
Decomposed

13. 7. Nobel Prize 2021 (10.2021)
• This year’s Nobel Prize in Chemistry was
awarded to David MacMillan and Benjamin List
‘for the development of asymmetric organic
catalysis’. (chiral catalyst )
• Organocatalysis is a unique tool for building
molecules.
• Benjamin List from the Max-Planck-Institut für
Kohlenforschung, Germany, and David
MacMillan from Princeton University, US.

14. 8. The Material that Feels (12.21)- Chicago
and Missouri
• This is so-called metamaterials. Such a metamaterial could work very well in
aviation, the space industry, medicine and in many other areas
•
• It is made from piezoelectric elements that are controlled by electrical circuits.
• Piezoelectric materials or piezoelectrics are the materials that can produce
electric energy upon application of mechanical stress
• What is piezoelectricity give example?- An example of applications in this area is
the electric cigarette lighter, where pressing a button causes a spring-loaded
hammer to hit a piezoelectric crystal, thereby producing a sufficiently high
voltage that electric current flows across a small spark gap, heating and igniting
the gas.
• Example : lead zirconate titanate (PZT), barium titanate, and lead titanate.
Gallium nitride and zinc oxide

15. 9. Eco-friendly Plastic from Salmon
Seed (12.21)
• Scientists Made an Eco-Friendly Plastic Using
DNA From Salmon Sperm- Chinese scientists
DNA (Salmon Sperm) + Vegetable oil
The result is a gel-like squishy substance - Hydrogel.
The production of this bioplastic can emit up to 97% less CO2
than the production of traditional polystyrene plastics.

16. 10. Graphene-based Lubricant (12.21)-
Italian researchers
• A novel graphene-based lubricant that can
be used in cars and motorbikes.
• Why graphene?- thermal, electrical, optical,
and mechanical properties,

17. 1.2: The Study of Chemistry
• What is chemistry?
• Chemistry is involved in everything we do.
• Chemistry is the science describing matter and its transformations
• Chemistry is called the central science because all scientists study chemicals at some level.
• Chemistry- is the scientific study of the properties and behavior of matter.
• It is a natural science that deals with –
(a) Atoms, molecules and ions
(b)Their composition, structure, properties, and behavior
(c) and the changes they undergo during a reaction with other substances.

18. History of Chemistry
Looking Closer: Alchemy:
the study of matter was known as alchemy and was practiced mainly in China,
Arabia, Egypt, and Europe.
Alchemy was a somewhat mystical and secretive approach
Greek "chemeia",
French "chimie",
German "Chemie",
Arabian "alchemy".
alchemy, meaning Black Earth",
Alchemy is the "Egyptian art“

19. Khem, Khemi, Kent, Kemi,
or Chemi (the word is variously
spelled) was the ancient name
of Egypt,
“The word chemistry in Greek should be wrote chemia,
and in Latin and English chemia and chemistry, not as
usual, chymia and chymistry.

20. In the eighth century A.D., Jābir ibn Hayyān, a Muslim
astronomer, philosopher and scientist, became one of the
first to use scientific methods to study materials.
Latinized name, Geber, he is known as the "father of
chemistry." He is thought to be the author of describing
methods of distillation, crystallization, sublimation and
evaporation.
His categories were:
“Spirits” — materials that would vaporize when heated.
"Metals" — including iron, tin, copper, and lead.
Non-malleable substances — materials that could be
made into powders, such as stone.

21. Antoine Lavoisier, "The Father of
Modern Chemistry".
Law of Conservation of Mass

22. 1.3: The Scientific Method

24. What is the Difference Between
Hypothesis, Theory, and Law
• A hypothesis is a researched and reasonable guess
about why something happens. It needs to be tested.
• A scientific theory is something that answers why and
it has been tested repeatedly and has so far always
been true.
• A law is a mathematical statement that tells how
something happens. A law typically looks like a short
mathematical equation.

25. Scientific statement
• Hypothesis: tentative explanation of observations that
acts as a guide for gathering and checking information
• Theory: well-substantiated, comprehensive, testable
explanation of a particular aspect of nature
Law: statement that summarizes a vast number of
experimental observations, and describes or predicts
some aspect of the natural world

26. How Scientists Study Chemistry

27. 1.4: Classifications of Matter

28. Matter
• Has mass (measured as weight)
• Occupies space (measured as volume)
Energy
• Rest of the “normal stuff” in the universe is energy, e.g., light
• Matter and energy are related
E = mc2

29. Modern astrophysics suggests…
• Matter and energy are about 5% of the
universe
• Dark matter is another 25%
• Dark Energy is the remaining 70%
• Or we don’t quite understand how physics
works at a universal scale!

30. 1.5: The Three States of Matter,

33. 1.6: Physical and Chemical Properties of
Matter

37. Changes in Chemistry

38. Chemical changes
• Chemical bonds are broken
• Atoms rearrange themselves
• New chemical bonds form

39. Chemical changes
• Chemical bonds are broken
• Atoms rearrange themselves
• New chemical bonds form
C3H8 + 5 O2 
Propane gas Molecular
oxygen

40. Chemical changes
• Chemical bonds are broken
• Atoms rearrange themselves
• New chemical bonds form
C3H8 + 5 O2  3 CO2 + 4 H2O
Propane gas Molecular
oxygen
Carbon
dioxide
Water
vapor

41. Physical changes
• Associated with changes in state (gas, liquid, solid,
solution)
• No chemical changes occur
Water freezes to ice
Ice melts to water
(It’s H2O before and after)
Sugar dissolves in water
Water evaporates leaving sugar
(It’s C12H22O11 before and after)

42. A burning Candle is…
1. A chemical change
2. A physical change
3. Both

43. A burning Candle is…
1. A chemical change
2. A physical change
3. Both

44. 1.7 : Measurement
• Chemists measure the properties of matter using
a variety of devices or measuring tools
• These devices are expressed as quantities.
• A quantity is an amount of something and
consists of a number and a unit
• The number tells us how many and the unit tells
us what the scale of measurement is.

45. • For example, when a distance is reported as
“5.2 kilometers,”
Here
• 5.2- Number
• Kilometers- unit
• Both a number and a unit must be included to express
a quantity properly.
•

46. Exercise 1
Identify the number and the unit in each quantity.
(a) one dozen eggs
(b) 2.54 centimeters
(c) a box of pencils
(d) 88 meters per second
• Answer a: The number is one, and the unit is dozen.
• Answer b: The number is 2.54, and the unit is centimeter.
• Answer c: The number 1 is implied because the quantity is only a box. The unit is
box of pencils.
• Answer d: The number is 88, and the unit is meters per second.
• Note that in this case the unit is actually a combination of two units: meters and
seconds.

47. Question: What are the two
necessary parts of a quantity?
Answer: The two necessary parts
are the number and the unit
.

48. 1.8: The Importance of Units
• Definition of unit: Unit is a quantity of a constant magnitude which is used to
measure the magnitude of other quantities of the same nature.
• Importance of units in the measurements:
• (i) Measurement of any physical quantity without a unit is meaningless.
• (ii) Unit establishes a relation between different measures of the same quantity.
• Fundamental unit: These are the units which do not depend on any other units or
which cannot be related to any other fundamental units.
• Derived unit: Those units which depend on the fundamental units or which can be
expressed in terms of fundamental units are known as derived units.

49. Unit Systems
• Metric
• Systeme International d’Unites (SI)
• English

50. Basic metric system
• Length in meters (m)
• Volume in cubic meters (m3) or liters (L) or
cm3 (cc’s)
• Mass in grams (g)
• Time in seconds (s)

52. The Seven
Base
SI Units
Property Unit Abbreviation
length meter m
mass kilogram kg
time second s
amount mole mol
temperature kelvin K
electrical current ampere amp
luminous intensity candela cd

53. . Unit prefixes to learn..
giga- (G)
mega- (M)
kilo- (k)
deci- (d)
centi- (c)
milli- (m)
micro- (m)
nano- (n)
pico- (p)
109
106
103
10-1
10-2
10-3
10-6
10-9
10-12
1 ng = 10-9 g
1 Gg = 109 g
1 Mg = 106 g
1 kg = 103 g
1 dg = 10-1 g
1 cg = 10-2 g
1 mg = 10-3 g
1 mg = 10-6 g
1 pg = 10-12g
billions
millions
thousands
tenths
hundredths
thousandths
millionths
billionths
trillionths

54. Unit prefixes to learn...
Here’s two nonsense phrases to
help you remember these prefixes
in order
Gee!
Megan
killed
Desi’s
scent.
Millie
microwaved
Nan’s
Piccolo.
giga- (G)
mega- (M)
kilo- (k)
deci- (d)
centi- (c)
milli- (m)
micro- (m)
nano- (n)
pico- (p)
109
106
103
10-1
10-2
10-3
10-6
10-9
10-12
billions
millions
thousands
tenths
hundredths
thousandths
millionths
billionths
trillionths

55. Unit prefixes to learn...
giga- (G)
mega- (M)
kilo- (k)
deci- (d)
centi- (c)
milli- (m)
micro- (m)
nano- (n)
pico- (p)
109
106
103
10-1
10-2
10-3
10-6
10-9
10-12
1 ng = 10-9 g
1 Gg = 109 g
1 Mg = 106 g
1 kg = 103 g
1 dg = 10-1 g
1 cg = 10-2 g
1 mg = 10-3 g
1 mg = 10-6 g
1 pg = 10-12g
billions
millions
thousands
tenths
hundredths
thousandths
millionths
billionths
trillionths

56. Unit prefixes to learn...
giga- (G)
mega- (M)
kilo- (k)
deci- (d)
centi- (c)
milli- (m)
micro- (m)
nano- (n)
pico- (p)
109
106
103
10-1
10-2
10-3
10-6
10-9
10-12
1 ng = 10-9 g
1 Gg = 109 g
1 Mg = 106 g
1 kg = 103 g
1 dg = 10-1 g
1 cg = 10-2 g
1 mg = 10-3 g
1 mg = 10-6 g
1 pg = 10-12g
billions
millions
thousands
tenths
hundredths
thousandths
millionths
billionths
trillionths
Find the best prefix by looking for an exponent equal to or smaller than your value.
We have 3.27 x 10-5, so

57. Unit prefixes to learn...
giga- (G)
mega- (M)
kilo- (k)
deci- (d)
centi- (c)
milli- (m)
micro- (m)
nano- (n)
pico- (p)
109
106
103
10-1
10-2
10-3
10-6
10-9
10-12
1 ng = 10-9 g
1 Gg = 109 g
1 Mg = 106 g
1 kg = 103 g
1 dg = 10-1 g
1 cg = 10-2 g
1 mg = 10-3 g
1 mg = 10-6 g
1 pg = 10-12g
billions
millions
thousands
tenths
hundredths
thousandths
millionths
billionths
trillionths
Find the best prefix by looking for an exponent equal to
or smaller than your value. We have 3.27 x 10-5, so

58. Unit prefixes to learn...
giga- (G)
mega- (M)
kilo- (k)
deci- (d)
centi- (c)
milli- (m)
micro- (m)
nano- (n)
pico- (p)
109
106
103
10-1
10-2
10-3
10-6
10-9
10-12
1 ng = 10-9 g
1 Gg = 109 g
1 Mg = 106 g
1 kg = 103 g
1 dg = 10-1 g
1 cg = 10-2 g
1 mg = 10-3 g
1 mg = 10-6 g
1 pg = 10-12g
billions
millions
thousands
tenths
hundredths
thousandths
millionths
billionths
trillionths

59. Temperature Systems
• Metric: Celsius (or centigrade)
• SI: Kelvin
• English: Fahrenheit

60. Celsius vs. Kelvin
• Both scales have the same size of degree
• 100 steps between freezing point and boiling
point of water
Celsius goes from 0 to 100
Kelvin goes from 273 to 373

61. Fahrenheit Scale
• Has 180 steps between freezing and boiling
points of water
1o Celsius = 1.8o Fahrenheit
• The scales also differ in their starting points
32 oF = 0 oC

62. Temperature Scales
Fahrenheit Celsius Kelvin

63. Freezing Point of Water
Fahrenheit Celsius Kelvin
0
32 273
Water freezes

64. Boiling Point of Water
Fahrenheit Celsius Kelvin
212 100 373
Water boils
0
32 273
Water freezes

65. Absolute Zero
Fahrenheit Celsius Kelvin
-459 -273 0
212 100 373
Water boils
Absolute
zero
0
32 273
Water freezes

66. Body Temperature
Fahrenheit Celsius Kelvin
-459 -273 0
212 100 373
Water boils
Absolute
zero
0
32 273
Water freezes
98.6 37 310

67. Crossover Point
Fahrenheit Celsius Kelvin
-459 -273 0
212 100 373
Water boils
Absolute
zero
0
32 273
Water freezes
-40 -40 233
98.6 37 310

68. Crossover Point
Fahrenheit Celsius Kelvin
-459 -273 0
212 100 373
Water boils
Absolute
zero
0
32 273
Water freezes
-40 -40 233
98.6 37 310
Fahrenheit and Celsius thermometers read
the same at -40o!

69. K = oC + 273
oC = K - 273
Celsius/Kelvin Conversions

70. If the temperature outside is 263 K, what
season is it? (Calculate the equivalent oC)
1. Summer
2. Fall
3. Winter
4. Spring

71. oC = K - 273
We’ll use the “oC =“
form since we want our
answer in oC.
If the temperature outside is
263 K, what season is it?
(Calculate the equivalent oC)
1. Summer
2. Fall
3. Winter
4. Spring

72. oC = K - 273
oC = 263 - 273
If the temperature outside is
263 K, what season is it?
(Calculate the equivalent oC)
1. Summer
2. Fall
3. Winter
4. Spring

73. oC = K - 273
oC = 263 - 273
If the temperature outside is
263 K, what season is it?
(Calculate the equivalent oC)
1. Summer
2. Fall
3. Winter
4. Spring

74. oC = K - 273
oC = 263 - 273
oC = - 10 (Brr! It feels
…………like winter!)
If the temperature outside is
263 K, what season is it?
(Calculate the equivalent oC)
1. Summer
2. Fall
3. Winter
4. Spring

75. oC = K - 273
oC = 263 - 273
oC = - 10 (Brr! It feels
…………like winter!)
If the temperature outside is
263 K, what season is it?
(Calculate the equivalent oC)
1. Summer
2. Fall
3. Winter
4. Spring

76. Fahrenheit Scale
• Has 180 steps between freezing and boiling
points of water
1o Celsius = 1.8o Fahrenheit
• The scales also differ in their starting points
32 oF = 0 oC

77. Crossover Point
Fahrenheit Celsius Kelvin
-459 -273 0
212 100 373
Water boils
Absolute
zero
0
32 273
Water freezes
-40 -40 233
98.6 37 310

78. Celsius/Fahrenheit Conversions
o F = (1.8 x oC) + 32

79. Celsius/Fahrenheit Conversions
o F = (1.8 x oC) + 32
(oF - 32)
1.8
o C =

80. Celsius/Fahrenheit Conversions
o F = (1.8 x oC) + 32
(oF - 32)
1.8
o C =
Here’s the adjustment for the
difference in degree size (180
steps vs. 100 steps)
Some books use 9/5 or 5/9
instead of the 1.8

81. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?

82. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(oF - 32)
1.8
o C =

83. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(oF - 32)
1.8
o C =
We use this form
because we want our
answer in oC

84. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(-3 - 32)
1.8
o C = =
-35
1.8
= -19.4444444 oC

85. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(-3 - 32)
1.8
o C = =
-35
1.8
= -19.4444444 oC
In subtracting, sig fig rules say retain the
fewest decimal places

86. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(-3 - 32)
1.8
o C = =
-35
1.8
= -19.4444444 oC
2 s.f.
2 s.f.

87. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(-3 - 32)
1.8
o C = =
-35
1.8
= -19.4444444 oC = -19 oC
2 s.f.
2 s.f.
2 s.f.

88. Check your answer...
Fahrenheit Celsius Kelvin
-459 -273 0
212 100 373
Water boils
Absolute
zero
0
32 273
Water freezes
-40 -40 233
98.6 37 310
-3 -19

89. A Sample Calculation…..
• On January 23rd, 2008 the overnight low
temperature at the Missoula International airport
was -3 oF.
What is the equivalent temperature on the
Celsius scale?
(-3 - 32)
1.8
o C = =
-35
1.8
= -19.4444444 oC = -19 oC
You get -20.8 oC if you
forget to include
parens!

90. If the temperature is 16oC, what is this in
oF?
1. -8.9 oF
2. 86.4 oF
3. 60.8
4. 61

91. If the temperature is 16oC, what
is this in oF?
1. -8.9 oF
2. 86.4 oF
3. 60.8
4. 61
o F = (1.8 x oC) + 32
o F = (1.8 x 16) + 32
o F = (28.8) + 32

92. If the temperature is 16oC, what
is this in oF?
1. -8.9 oF
2. 86.4 oF
3. 60.8
4. 61
o F = (1.8 x oC) + 32
o F = (1.8 x 16) + 32
o F = (28.8) + 32
o F = 60.8

93. If the temperature is 16oC, what
is this in oF?
1. -8.9 oF
2. 86.4 oF
3. 60.8
4. 61
o F = (1.8 x oC) + 32
o F = (1.8 x 16) + 32
o F = (28.8) + 32
o F = 60.8
o F = 61
(with sig figs – 28.8 should
be rounded up to 29)

94. If the temperature is 16oC, what
is this in oF?
1. -8.9 oF
2. 86.4 oF
3. 60.8
4. 61
o F = (1.8 x oC) + 32
o F = (1.8 x 16) + 32
o F = (28.8) + 32
o F = 60.8
o F = 61

95. 1.9: Handling Numbers
Handling of numbers associated with measurements :
1.Scientific Notation
2. Significant Number

96. Scientific Notation
• Scientific notation allows us to express
very large and very small numbers using
powers of 10.
• A very large number:
• 579, 000, 000, 000
• and express it using scientific notation

97. • A very large number:
• 579, 000, 000, 000
• and express it using scientific notation.
• A coefficient, which is a number between 1 and 10
• that will be multiplied by 10 raised to some power.
• Our coefficient is: 5.79
• 5 . 7 9 0 0 0 0 0 0 0 0 0
• ↑ ↑
• How many positions are there?

98. • there are 11 positions between our decimal
and the end of the original number.
• This means that our coefficient, 5.79,
• will be multiplied by 10 raised to the 11th
power.
• Our number expressed in scientific notation is:
• 5.79 x 1011

104. 1. Write 25,700,000,000,000 in scientific notation.
Answer:
2.57×1013.
2. Write 0.0000000005 in scientific notation.
Answer:
is 5×10−10.

105. Express each number in scientific
notation
(a) 67,000,000,000
(b) 1,689
(c) 12.6
Answer a:
Moving the decimal point 10 places to the left gives 6.7 × 1010.
Answer b:
The decimal point is assumed to be at the end of the number, so moving it
three places to the left gives 1.689 × 103.
Answer c:
In this case, we need to move the decimal point only one place to the left, which
yields 1.26 × 101.
•

106. Express each number in scientific notation.
• (a) 1,492
• (b) 102,000,000
• (c) 101,325
• Answer a: Moving the decimal point 3 places to the left gives 1.492
× 103.
• Answer b: The decimal point is assumed to be at the end of the
number, so moving it 8 places to the left gives 1.02 × 108.
• Answer c: Moving the decimal point 5 places to the left yields
1.01325 × 105.

107. Convert Scientific Notation to Standard Form
• Express each number in standard, or
convention
(a) 5.27 × 104
(b) 1.0008 × 106
• Answer a: Moving the decimal four places to
the right and adding zeros give 5,2700.
• Answer b: Moving the decimal six places to
the right and adding zeros give 1,000800.

108. Express each number in standard, or conventional
notation.
(a) 6.98×108
(b) 1.005×102
• Answer a: Moving the decimal point eight places
to the right and adding zeros give 698,000,000.
• Answer b: Moving the decimal point two places
to the right gives 100.5

110. Significant Figures
How many digits should be reported for the
length of this object?
The significant figures of a measured quantity are
defined as all the digits known with certainty and
the first uncertain, or estimated, digit.

111. Figure 1. To measure the volume of liquid in this graduated cylinder, you must
mentally subdivide the distance between the 21 and 22 mL marks into tenths of
a milliliter, and then make a reading (estimate) at the bottom of the meniscus.
All of the digits in a measurement, including the uncertain last digit, are
called significant figures or significant digits.

114. Rule for Addition and subtraction
We drop the last digit—the 1—because it is not significant to the final answer.

115. Rounding up
 The rule in addition and subtraction is that the answer is
given the same number of decimal places as the term with
the fewest decimal places.

116. Multiplication and division
The final answer, limited to four significant figures, is 4,094. The first digit
dropped is 1, so we do not round up.
 The rule in multiplication and division is that the final
answer should have the same number of significant figures
as there are in the number with the fewest significant
figures.

119. Accuracy, and precision
Accuracy is a measure of how close a result is to the true value.
Precision is a measure of how repeatable the result is.

121. 1.10: Dimensional Analysis in Solving
Problems: The Factor-Label Method
• Uses conversion factors to go between unit
systems

123. Accuracy
Accuracy is how close a measured value is
to the actual (true) value.
Precision
Precision is how close the measured values
are to each other.

125. The Factor-Label Method
• Uses conversion factors to go between unit
systems
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =

126. • In use, a conversion factor will appear as a
fraction
Conversion Factors
1.000 mile
1.609 km
or
1.609 km
1.000 mile

127. Sample calculation...
• In the Olympics, how long is the marathon
event in kilometers? I know it’s 26.22 miles
long (26 miles 385 yds).
26.22 miles km
x
1.000 mile
1.609 km
42.187980 Round to correct sig
figs
4 s.f.
4 s.f.
4 s.f.

128. Sample calculation...
• In the Olympics, how long is the marathon
event in kilometers? I know it’s 26.22 miles
long (26 miles 385 yds).
26.22 miles km
x
1.000 mile
1.609 km
42.187980 Drop uncertain digits
with rounding
4 s.f.
4 s.f.
4 s.f.

129. Sample calculation...
• In the Olympics, how long is the marathon
event in kilometers? I know it’s 26.22 miles
long (26 miles 385 yds).
26.22 miles km
x
1.000 mile
1.609 km
42.19 Drop uncertain digits
with rounding
4 s.f.
4 s.f.
4 s.f.

130. Sample calculation...
• In the Olympics, how long is the marathon
event in kilometers? I know it’s 26.22 miles
long (26 miles 385 yds).
26.22 miles km
x
1.000 mile
1.609 km
= 42.19

131. Another calculation...
• This example shows how to use the metric
prefix table…
How many micrograms in 4.5 x 10-5 g?
4.5 x 10-5 g mg
x
10-6 g
1.0 mg
Orient so that units cancel

132. Another calculation...
• This example shows how to use the metric
prefix table…
How many micrograms in 4.5 x 10-5 g?
4.5 x 10-5 g mg
x
10-6 g
1.0 mg
= 45
0.000 045 g
The answer makes
sense when
viewed like this...

133. Another calculation...
• This example shows how to use the metric
prefix table…
How many micrograms in 4.5 x 10-5 g?
4.5 x 10-5 g mg
x
10-6 g
1.0 mg
= 45
0.000 045 g
milli
The answer makes
sense when
viewed like this...

134. Another calculation...
• This example shows how to use the metric
prefix table…
How many micrograms in 4.5 x 10-5 g?
4.5 x 10-5 g mg
x
10-6 g
1.0 mg
= 45
0.000 045 g
milli micro
The answer makes
sense when
viewed like this...

135. Another calculation...
• This example shows how to use the metric
prefix table…
How many micrograms in 4.5 x 10-5 g?
4.5 x 10-5 g mg
x
10-6 g
1.0 mg
= 45
0.000 045 g
milli micro
The answer makes
sense when
viewed like this...

136. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =

137. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog 73 mL soln

138. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
73 mL soln

139. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
Units cancel
73 mL soln

140. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
=
31.7 x 2.3
1.0
Do the math:
73 mL soln

141. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
=
72.91
Do the math:
73 mL soln

142. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
=
72.91
Round to 2 s.f.:
73 mL soln

143. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
=
73
Round to 2 s.f.:
73 mL soln

144. The Factor-Label Method
• A 31.7-kg dog needs valium to suppress
hysteria from 4th of July fireworks. The
prepared solution needs to be administered
at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
=
73
Round to 2 s.f.:
73 mL soln

145. The Factor-Label Method/ Dimensional
Analysis
• A 31.7-kg dog needs valium to suppress hysteria from 4th
of July fireworks. The prepared solution needs to be
administered at the rate of 2.3 mL/kg. How many mL of
valium solution should be injected?
Starting
quantity
Conversion
factor(s)
Equivalent
quantity
x =
31.7 kg dog x
2.3 mL soln
1.0 kg dog
= 73 mL soln

146. • How many centimeters are there in 3.55 m?
• Lets try-
• We first write the quantity are given, 3.55 m.
• Then we multiply this quantity by a conversion factor, which is
the same as multiplying it by 1.
• We can write 1 as and multiply:
•
Rule : Quantity (in old units) × Conversion
Factor = Quantity (in new units)

147. A Concept Map for Conversions. This is how you construct a conversion factor
to convert from one unit
to another.

148. quantity (in old units) × conversion factor =
quantity (in new units)
This is how you construct a conversion factor to convert
from one unit to another.

149. Problem : Write a concept map (a plan) for how you would
convert 1.0×1012 nanoliters (nL) to kiloliters (kL).
Solution : Concept Map:
Step-1: Convert the given quantity (nanoliters, nL) to liters.
Step-2: Then convert liters to kiloliters.
Rule : Quantity (in old units) × Conversion Factor = Quantity (in new units)
Two Step methods

150. Problem : How much does it cost to drive a car from Little Rock
to Memphis (137 miles) if a car gets 21 mpg and the price of gas
is $2.54/gal
• Solution : There are two equivalence statements here, along
with the distance needed to be travelled
• 137 miles
• 21 miles=1 gallon
• $ 2.54=1 gallon
137 𝑚𝑖𝑙𝑒𝑠
1 𝑔𝑎𝑙𝑙𝑜𝑛
21 𝑚𝑖𝑙𝑒𝑠
& 2.54
𝑔𝑎𝑙𝑙𝑜𝑛
= &
16.57

151. Problem : Convert 25.0 mL to L.
Solution:

152. Problem: If 2 Red is equal to 1 blue, what about 4 Reds
Solution

153. Problem : If the gold block weighs 12 kilograms, how many
pounds does it weigh?
Solution : The relationship 1.0 lbs = 0.45 kg is first rewritten as a ratio.
Then, we multiply our known value, 12 kg, by the ratio 1.0 lbs/0.45 kg.

154. Problem : How many Iodide ions are produced when 4
mols of CaI2 are fully dissolved?
Since there are two mols of Iodide (I– ) for every one mol of Calcium Iodide
(CaI2), the following ratio can be written as -
Conversion Factor =
Ans = 8 mol

155. Problem: Express 24.0 cm in inches.
Staring Quantity (6.00) contains 3 sig. fig.

156. Problem: How many seconds are in 2.0 years?

158. • Problem: How many atoms of hydrogen can be found in 45
g of ammonia, NH3?
We will need three unit factors to do this calculation, derived from the
following information:
• a. 1 mole of NH3 has a mass of 17 grams.
• b. 1 mole of NH3 contains 6.02 x 1023 molecules of NH3.
• c. 1 molecule of NH3 has 3 atoms of hydrogen in it.
Staring Quantity (45 g) contains 2 sig. fig.

160. What we Learned from Chapter-1
1. Recent significant discoveries in 21 century
2. Scientific method
3. State of Matters and Change of Chemical and
Physical Properties
4. Measurement and Unites of measurement
5. Scientific Notation
6. Significant Figure
7. Rounding Rule
8. Accuracy and Precision
9. The Factor-Label Method/ Dimensional Analysis
Some Solution of Problems

161. Thank you all