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MODULE 1 NOTES

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COLLEGE OF PHARMACY
1.1 CHEMISTRY: THE STUDY OF MATTER
Chemistry is the field of study concerned with matter's characteristics, composition, and transformations.
Matter - is anything that has mass and occupies space.
Matter includes all things—both living and nonliving—that can be seen (such as plants, soil, and rocks) and things that
cannot be seen (such as air and bacteria). Various forms of energy such as heat, light, and electricity are not considered to
be matter
An iron gate rusting, a chocolate cake baking, the diagnosis and treatment of a heart attack, the propulsion of a jet airliner,
and the digesting of food all fall within the realm of chemistry
Mass - the amount of matter present in a sample.
1.2
PHYSICAL STATES OF MATTER
The classification of a given matter sample in terms of physical state is based on whether its shape and volume are definite or
indefinite.
a. Solid is the physical state characterized by a definite shape and a definite volume.
b. Liquid is the physical state characterized by an indefinite shape and a definite volume. A liquid always takes the shape of its
container to the extent that it fills the container.
c. Gas is the physical state characterized by an indefinite shape and an indefinite volume. A gas always completely fills its
container, adopting both the container’s volume and its shape.
Water is one of the few substances found in all three of its physical states:
 solid ice, liquid water, and gaseous steam
1.3 PROPERTIES OF MATTER
Various kinds of matter are distinguished from each other by their properties.
Property is a distinguishing characteristic of a substance that is used in its identification and description.
Two general types:
1. Physical property is a characteristic of a substance that can be observed without changing the basic identity of the
substance.
Common physical properties include color, odor, physical state (solid, liquid, or gas), melting point, boiling point, and
hardness.
2.
Chemical property is a characteristic of a substance that describes the way the substance undergoes or resists change
to form a new substance. For example, copper objects turn green when exposed to moist air for long periods of time.
E X A M P L E 1.1: Classifying Properties as Physical or Chemical. Classify each of the following properties for selected
metals as a physical property or a chemical property.
a. Iron metal rusts in an atmosphere of moist air.
Chemical property. The interaction of iron metal with moist air produces a new substance (rust).
b. Mercury metal is a liquid at room temperature.
Physical property. Visually determining the physical state of a substance does not produce a new substance.
c. Nickel metal dissolves in acid to produce a light green solution.
Chemical property. A change in color indicates the formation of a new substance.
d. Potassium metal has a melting point of 63°C.
Physical property. Measuring the melting point of a substance does not change the substance’s composition.
1.4 CHANGES IN MATTER
Changes in matter are common and familiar occurrences. Changes take place when food is digested, paper is burned, and a
pencil is sharpened. Like properties of matter, changes in matter are classified into two categories:
1. Physical change is a process in which a substance changes its physical appearance but not its chemical composition.
A new substance is never formed as a result of a physical change.
Most common type of physical change: Melting, freezing, evaporation, and condensation
2. Chemical change is a process in which a substance undergoes a change in chemical composition.
E X A M P L E 1.2 Correct Use of the Terms Physical and Chemical in Describing Changes.
Complete each of the following statements about changes in matter by placing the word physical or chemical in the blank.
a. The fashioning of a piece of wood into a round table leg involves a ___change.
Physical. The table leg is still wood. No new substances have been formed.
b. The vigorous reaction of potassium metal with water to produce hydrogen gas is a ___change.
Chemical. A new substance, hydrogen, is produced.
c. Straightening a bent piece of iron with a hammer is an example of a ___change.
Chemical. A new substance, hydrogen, is produced.
d. The ignition and burning of a match involve a ___change.
Chemical. A new substance, hydrogen, is produced.
1.
1.5
PURE SUBSTANCES AND MIXTURES
Pure substance is a single kind of matter that cannot be separated into other kinds of matter by any physical means.
All samples of a pure substance contain only that substance and nothing else.
Example: Pure water, Pure sucrose (table sugar) contains only that substance and nothing else.
Chapter 1: Basic Concepts of Matter
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COLLEGE OF PHARMACY
2.
Mixture is a physical combination of two or more pure substances in which each substance retains its own chemical
identity. Components of a mixture retain their identity because they are physically mixed rather than chemically
combined.
Sub classification is based on visual recognition of the mixture’s components:
a. Homogeneous mixture is a mixture that contains only one visibly distinct phase (part), which has uniform
properties throughout.
b. Heterogeneous mixture is a mixture that contains visibly different phases (parts), each of which has different
properties.
1.
2.
1.6
ELEMENTS AND COMPOUNDS
Element is a pure substance that cannot be broken down into simpler pure substances by chemical means such as a
chemical reaction, an electric current, heat, or a beam of light.
The metals gold, silver, and copper are all elements.
Compound is a pure substance that can be broken down into two or more simpler pure substances by chemical means.
Example: Water (H₂O) is a compound. By means of an electric current, water can be broken down into the gases
hydrogen and oxygen.
1.7 DISCOVERY AND ABUNDANCE OF THE ELEMENTS
The discovery and isolation of the 117 known elements, the building blocks for all matter, have taken place over a period of
several centuries. Most of the discoveries have occurred since 1700, the 1800s being the most active period.
a. 88 of the 117 elements occur naturally, and 29 have been synthesized in the laboratory by bombarding
samples of naturally occurring elements with small particles.
b. Oxygen, the most abundant element in Earth’s crust, was isolated in pure form for the first time in 1774 by the
English chemist and theologian Joseph Priestly (1733–1804).
c. Discovery years for the other “TOP FIVE” elements of Earth’s crust:
i.
1824 (Silicon)
ii.
1827 (Aluminum)
iii.
1766 (Hydrogen)
iv.
1808 (Calcium)
v.
Oxygen
d. Elemental Composition of the Human Body: Only four elements are found in the human body.
i.
Hydrogen, carbon, and nitrogen are all much more abundant than in Earth’s crust, and oxygen is
significantly less abundant than in Earth’s crust
ii.
Carbohydrates (CHO), fats, and proteins (CHON)

Nutrients required by the human body in large amounts, are all sources of carbon(C),
hydrogen(H), and oxygen(O).
Proteins are the body’s primary nitrogen (N) source.
1.7
NAMES AND CHEMICAL SYMBOLS OF THE ELEMENTS
Chemical symbol is a one- or two-letter designation for an element derived from the element’s name.
NOTE!!!
1. The first letter of a chemical symbol is always capitalized and the second is not.
2. Two-letter chemical symbols are often, but not always, the first two letters of the element’s name.
History of Periodic Table:
1. Antoine Lavoisier – first extensive list of elements (approx.. 33)
2. John Dobereiner - was a German scientist who developed the Law of Triads.
3. John Newlands - Ordered elements according to increasing atomic mass in a chart that demonstrated periodic
properties of the elements and added rule of octaves. (Law of Octave)
4. Dmitri Mendeleev – Father of Periodic Table
Latin Names of Chemical Elements:
1. Sodium (Na – Natrium)
2. Potassium (K – Kalium)
3. Iron (Fe – Ferrum)
4. Copper (Cu – Cuprum)
5. Silver (Ag – Argentum)
6. Tin (Sn – Stannum)
7. Antimony (Sb – Stibium)
8. Tungsten (W – Wolfram) - translates into English as “heavy stone”
9. Gold (Au – Aurum)
10. Mercury (Hg – Hydrargyrum) - Greek hydrargyros, which means “water silver.”
11. Lead (Pb – Plumbum)






The elements mercury, uranium, and neptunium are all named for planets.
Germanium is named after the native country of its German discoverer.
Francium and Polonium are named after France and Poland.
Helium gets its name from the Greek word helios, for “sun,”
Chlorine’s name is derived from the Greek chloros, denoting “greenish-yellow,”
Iridium gets its name from the Greek iris, meaning “rainbow”
Chapter 1: Basic Concepts of Matter
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COLLEGE OF PHARMACY
1.8
ATOMS AND MOLECULES
Atom is the smallest particle of an element that can exist and still have the properties of the element.
Molecule is a group of two or more atoms that functions as a unit because the atoms are tightly bound together
Molecules are classified into two categories:
a. Homoatomic molecule is a molecule in which all atoms present are of the same kind.
Some examples: hydrogen gas, oxygen gas, nitrogen gas, phosphorus molecule.
b. Heteroatomic molecule is a molecule in which two or more kinds of atoms are present.
1.10 CHEMICAL FORMULAS
Chemical formula is a notation made up of the chemical symbols of the elements present in a compound and numerical
subscripts that indicate the number of atoms of each element present in a molecule of the compound.
Examples:
1. The chemical formula for the compound aspirin is C₉H₈O₄. It contains 3 elements:
2.
Carbon – 9 atoms
Hydrogen – 8 atoms
Oxygen – 4 atoms
A total of 21 atoms
When only one atom of a particular element is present in a molecule of a compound, that element’s symbol is written without a
numerical subscript in the formula for the compound.
Acetone - C₃H₆O
Carbon – 3 atoms
Hydrogen – 6 atoms
Oxygen – 1 atoms
A total of 10 atoms
Types of Chemical Formula:
1. Molecular formula is a representation of a molecule that uses chemical symbols to indicate the types of atoms followed by
subscripts to show the number of atoms of each type in the molecule.
2. Empirical formula is a formula that shows the elements in a compound in their lowest whole-number ratio.
MOLECULAR FORMULA
C₄H₈
COMPOUND
Ethene
4 𝑐𝑎𝑟𝑏𝑜𝑛
8 ℎ𝑦𝑑𝑟𝑜𝑔𝑒𝑛
4
1 𝑐𝑎𝑟𝑏𝑜𝑛
÷ 4 = 2 ℎ𝑦𝑑𝑟𝑜𝑔𝑒𝑛
EMPIRICAL FORMULA
CH₂
Cyanuric triazide
C₃H₁₂
C
C
C
CH₄
C
3 𝑐𝑎𝑟𝑏𝑜𝑛
12 𝑛𝑖𝑡𝑟𝑜𝑔𝑒𝑛
3
1 𝑐𝑎𝑟𝑏𝑜𝑛
3
4 𝑛𝑖𝑡𝑟𝑜𝑔𝑒𝑛
÷ =
P₃N₅
C₅H₁₂
P₃N₅
If the ratio of atoms in the Molecular
formula can’t be simplified any more,
the Empirical Formula is the same as
the Molecular Formula.
C₅H₁₂
Chapter 1: Basic Concepts of Matter
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