CHEM 110 How to reach me?

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CHEM 110

General Chemistry King Abdul Aziz University

Jeddah KSA

1

How to reach me?

Prof. Hadi M. Marwani

Professor of Analytical and Environmental Chemistry

2

• Faculty of Science, Chemistry Department

• Room 362.

• E-mail address: [email protected]

• Website: www.kau.edu.sa/hmarwani

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Text Book

• Any General Chemistry Book

• Selected textbooks:

• Chemistry 10

^th

Edition by Raymond Chang

• General Chemistry System, Marwani and Albar at Dar Hafez

• General Chemistry, McMurray Ch i t Whitt

3

• Chemistry, Whitten

• Chemistry, By C. Mortimer, 6

^th

edition

Grading System

30% First midterm 30% Second midterm

40% Final exam

4

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Grading System

95 – 100 % A+

90 95 % A 90 – 95 % A 85 – 89 % B+

80 – 84 % B 75 – 79 % C+

70 – 74 % C

5

65 – 69 % D+

60 – 64 % D

< 60 % F (Fail)

Chemistry: The Study of Change

Chapter 1

General Chemistry

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What is Chemistry?

Chemistry is defined as "the study of matter and its change"

Matter Matter

Matter is everything around us.

Matter is anything that has a mass and occupy a space.

Matter exists in three states: solid, liquid and gas.

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Matter

Mixture Pure substance

Element Compounds Heterogeneous Homogeneous

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Classification of Matter

Matter

Anything with mass and volume.

Pure Substance

Matter with constant composition Mixture

Matter with variable composition Element

Substance made up of only one

type of atom

Compound Two or more elements that are

chemically combined

Heterogeneous Mixture Mixtures that are made up of more than one phase

Homogeneous Mixtures Also called

solutions. Mixtures that are made up of only one phase

9 Examples -

gold, silver, carbon, oxygen and hydrogen

Examples -water, carbon dioxide, sodium bicarbonate, carbon monoxide

Examples -sand, soil, chicken soup, pizza, chocolate chip cookies.

Examples -salt water, pure air, metal alloys, seltzer water.

Pure Substance:

A material with a constant composition such as NaCl, H₂O, H₂, CO₂, and O₂. Elements:

Any substance that contains only one kind of an atom, such as H₂and O₂. 2H₂O ---> 2H₂+ O₂

Symbols for Some Elements Name of

Element Symbol Name of

Element Symbol

Aluminum Al magnesium Mg

Bromine Br Neon Ne

Calcium Ca Nickel Ni

Carbon C Nitrogen N

Chlorine Cl Oxygen O

2 2 2

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Chlorine Cl Oxygen O

Copper Cu phosphorus P

Gold Au potassium K

Helium He Silicon Si

Hydrogen H Sodium Na

Iodine I Sulfur S

Iron Fe Tin Sn

Lead Pb Zinc Zn

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Example: Write the symbols for the following:

chlorine, copper, hydrogen, sodium, nickel, carbon, and oxygen.

• Answer:

hl i (Cl)

• chlorine (Cl)

• copper (Cu)

• hydrogen (H)

• sodium (Na)

• nickel (Ni)

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• nickel (Ni)

• carbon (C)

• oxygen (O)

• Compound is a material that consists of two or more

Examples of Some Chemical Formulas Compound Common

N Chemical

F l

elements united together in definite proportion.

• Compounds are represented by chemical formulas.

• Chemical formulashows the symbols of the elements that are combined to make the compound.

Name Formula calcium

carbonate chalk CaCO3

carbon dioxide dry ice CO2

hydrochloric acid muriatic acid HCl hydrogen sulfide rotten-egg

gas H₂S sodium hydrogen

carbonate baking soda NaHCO₃

12 carbonate

(or sodium bicarbonate)

sodium chloride table salt NaCl sodium nitrate fertilizer NaNO₃ sulfuric acid battery acid H2SO4

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• Mixtures - Mixtures are made up of two or more substances that are physically combined.

• The specific composition will vary from sample to sample.

Homogenous mixtures- you cannot distinguish between its component such as milk, apple juice, and air.

Heterogeneous mixtures- made up of more than one substance and they can be separated physically such as sandwich, smoke coming out

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y p p y y , g

of the car.

Physical and Chemical Properties

Physical propertiescan be observed or measured without changing the composition of matter.

Physical properties are used to observe and describe matter, such as appearance, texture, color, odor, melting point, boiling point, density, solubility, polarity, and many others.

density, solubility, polarity, and many others.

Chemical propertiesare only observable during a chemical reaction. For example, you might not know if sulfur is combustible unless you tried to burn it.

Mater Change

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Physical changeinvolves a change in the physical properties of the matter and it could be reversed, such as melting solid ice to liquid water.

Chemical changeinvolves a change in the chemical composition of the matter and it could not be reversed, such as burning sugar.

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Example

Classify each of the following changes as physical or chemical:

Melting Iron g Melting Ice Burning Paper Chopping Wood Mixing Salt & Water Breaking Glass

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Burning Wood

Mixing Peas & Carrots

Measurements

The International System of Measurements (SI)

PROPERTY UNIT SYMBOL

Length Meter m

Mass Kilogram kg

Time Second s

Amount Mole mol

Temperature Kelvin K

Electrical

Current Ampere A

Luminosity Candela Cd

Derived Units:Units that are

d f bi ti f

There are seven SI base units.

PROPERTY UNIT SYMBO

L DEFINITION

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made up of some combination of SI base units are called Derived Units.

L

Force Newton N kg m/s²

Pressure Pascal Pa N/m²

or kg/m s²

Energy Joule J kg m²/s²

or N m

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SI Prefixes:

used with the base units in order to increase or decrease the value that they represent.

PREFIX SYMBO L

NUMERICAL EQUIVALENT exa- E 1 000 000 000 000 000 000 (10¹⁸) peta- P 1 000 000 000 000 000 (10¹⁵) tera- T 1 000 000 000 000 (10¹²)

Giga G 1 000 000 000 (10⁹)

Mega M 1 000 000 (10⁶)

To remove a prefix from a value, Mega M 1 000 000 (10 )

Kilo K 1000 (10³)

hecto- H 100 (10²)

deca- Da 10 (10¹)

deci- D 0.1 (10^-1)

Centi C 0.01 (10^-2)

milli- M 0.001 (10^-3)

micro-  0.000 001 (10^-6) nano- N 0.000 000 001 (10^-9) To remove a prefix from a value,

insert the numerical value of the prefix in place of the symbol.

Example:

Convert 5.83 pm to meters

Replace "p" with x 10^-12

= 5.83 x 10^-12m

17 pico- P 0.000 000 000 001 (10^-12) femto- F 0.000 000 000 000 001 (10^-15)

atto- A 0.000 000 000 000 000 001 (10^-18) To insert a prefix into a value,

insert both the prefix and the inverse of its numerical value.

Example:

Convert 0.000462 g to milligrams (note that the inverse of milli is 10⁺³)

= 0.000462 x 10⁺³mg = 4.62 x 10^-1mg OR 0.462 mg

K =

⁰

C + 273.15 273 K = 0

⁰

C

0

F = 9 x

⁰

C + 32 5

273 K = 0

⁰

C 373 K = 100

⁰

C

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C 3

5

32

⁰

F = 0

⁰

C

212

⁰

F = 100

⁰

C

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Convert 172.9

⁰

F to degrees Celsius.

0

F = x 9

⁰

C + 32 5

0

F – 32 = F 32 = x C 9 x

⁰

C 5

x (

⁰

F – 32) =

⁰

C 9

5

0

C = x (

⁰

F – 32) 9

5

0

C 5 (172 9 32) 78 3

19

0

C = x (172.9 – 32) = 78.3 9

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Density

Density is an important property, which can be used to help determine the identity of an unknown substance.

) ml ( volume

) g ( densiy mass

A student determines that a piece of an unknown material has a mass of 5.854 g and a volume of 7.57 cm³. What is the density of the material, rounded to the correct number of significant figures?

) (

) cm ( 57 . 7

) g ( 854 . 5 ) cm ( volume

) g (

densiy mass ₃  ₃

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d = 0.77331571994 g/cm³

= 0.773 g/cm³