This document provides an introduction to general chemistry. It defines chemistry as the study of matter and its transformations. Matter is anything that has mass and occupies space, and can exist in different states such as solid, liquid, gas, and plasma. The document discusses physical and chemical properties of matter, as well as physical and chemical changes. It classifies matter as either pure substances like elements and compounds, or mixtures that are either homogeneous or heterogeneous. The key concepts covered include the states of matter, phase changes, and the classification of matter.

1. The Nature
of Chemistry
General Chemistry I

2. What is CHEMISTRY?
Chemistry is the science of molecules and their
transformations. It is the science not so much of the
one hundred elements but of the infinite variety of
molecules that may be built from them.

3. Chemistry is the study of the composition, structure,
and properties of matter and of changes
(transformations) that occur in matter. Often known
as the central science, it is a creative discipline
chiefly concerned with atomic and molecular
structure and its change, for instance through
chemical reactions.

4. Importance of Chemistry
Principles of chemistry are applicable in diverse areas,
such as weather patterns, functioning of the brain and
operation of a computer, production in chemical industries,
manufacturing fertilizers, alkalis, acids, salts, dyes,
polymers, drugs, soaps, detergents, metals, alloys, etc.,
including new material.

5. Importance of Chemistry
Plays an important role in meeting human needs for food,
healthcare products and other materials aimed at
improving the quality of life.
Provides methods for the isolation of lifesaving drugs from
natural sources and makes possible synthesis of such
drugs

6. Importance of Chemistry
Chemical principles have now become possible to design
and synthesize new materials having specific magnetic,
electric, and optical properties. This has led to the
production of superconducting ceramics, conducting
polymers, optical fibers, etc.

7. Importance of Chemistry
Chemistry has helped in dealing with some of the pressing
aspects of environmental degradation with a fair degree of
success.

8. COURSE CONTENT:
● Matter
● States of Matter
● Properties of Matter
● Changes in Matter
● Classification of Matter

9. Learning Objectives:
● Define matter.
● Differentiate the states of matter.
● Give examples of solids, liquids, gases, and plasma.
● Understand the transitions between states of matter.

10. Learning Objectives:
● Identify physical and chemical properties.
● Define physical change and list several common physical
changes.
● Define chemical change and list several indications that a
chemical change has taken place.

11. What is Matter?

12. MATTER
MASS and VOLUME
 Matter is anything that occupies space and has mass.
 It is composed of tiny building blocks known as "atoms".
 Matter can take different forms depending on the conditions.
COMPOSITIONANDPROPERTIES

13. COMPOSITION - the types and amounts of atoms that
make up a sample of matter

14. PROPERTIES - a characteristic that can be observed or
measured without changing the identity or composition of the
substance

15. PHYSICAL PROPERTIES - a characteristic that can be observed
or measured without changing the identity or composition of the substance.
Temperature
Mass
Pressure
Volume
State (solid, liquid, gas)
Melting and Boiling point
Thermal Conductivity
Electrical Conductivity
Density
Color and Shape
Hardness/brittleness
Heat Capacity

16. 1. Mass and Weight
Mass of a substance is the amount of matter present in it, while
weight is the force exerted by gravity on an object.
2. Volume
Volume is the amount of space occupied by a substance.
3. Melting and Boiling Point
Melting point is the temperature at which a solid changes into a
liquid while boiling point is the temperature at which a liquid
changes into a gas.

17. 4. Temperature
• Determines whether there can be heat energy transfer from one
object to another.
• Celsius temperature scale
• 0°C = Freezing point
• 100°C = Boiling point
• Fahrenheit temperature scale
• 32°F = Freezing point
• 212°F = Boiling point
(__°F − 32) × 5/9 = °C
• Fahrenheit to Celsius
• Celsius to Fahrenheit
(__°C × 9/5) + 32 = °F

18. CONCEPTUAL EXERCISE
1. Which is the higher temperature, 110°C or 180°F?
ANSWER: 110°C
(180°F − 32) × 5/9 = 82.22°C
110°C is higher than 82.22°C
2. Which is the lower temperature, 36°C or 100°F?
(36°C × 9/5) + 32 = 96.8°F
36°C/96.8°F is lower than 100°F
ANSWER: 36°C

19. 4. Density
The density of a substance is its amount of mass per unit volume.
Density = Mass/Volume
Mass is commonly measured in units of grams (g). Volume is
commonly expressed in cubic centimeters (cm3) or in milliliters (ml)
(1cm3 = 1 ml). Therefore, common units used to express density are
grams per milliliters (g/ml) and grams per cubic centimeter
(g/cm3).

20. Example: A typical brick has a mass of 2,268 g and occupies
a volume of 1,230 cm3. Using the equation, calculate the
density of the brick:
Densitybrick = Massbrick/Volumebrick
Densitybrick = 2,268 g/1,230 cm3
Densitybrick = 1.84 g/cm3

21. Physical properties used to describe matter can be classified as:

22. Intensive properties are bulk properties, which means
they do not depend on the amount of matter that is
present.
Extensive properties do depend on the amount of matter
that is present. An extensive property is considered
additive for subsystems.
The ratio between two extensive properties is an intensive property. For
example, mass and volume are extensive properties, but their ratio
(density) is an intensive property of matter.

23. CHEMICAL PROPERTIES - ability or inability of a substance to
combine with or change into one or more other substances i.e. ability of a
substance to undergo a chemical reaction
Oxidation states
Coordination Number
Chemical bonding
Reactivity
Heat of Combustion Flammability
Corrosivity
Toxicity
Acidity
Radioactivity

25. Classify each as a physical or chemical property:
1. Iron and oxygen form rust.
2. Iron is more dense than aluminum
3. Magnesium burns brightly when ignited.
4. Oil and water do not mix.
5. Mercury melts at -39°C.

26. STATES OF MATTER

27. Solid Solids have relatively rigid, with
definite volume and shape. In a
solid, the atoms and molecules
are attached to each other. They
vibrate in place but don’t move
around.

28. Liquid Liquids have definite volume but
are able to change shape by
flowing. In a liquid, the atoms
and molecules are loosely
bonded. They move around but
stay close together.

29. Gas
Gases have no definite volume
or shape. The atoms and
molecules move freely and
spread apart from one another.

30. Plasma
Plasma is sometimes referred to as the
fourth state of matter. A state, similar to a
gas, where the electrons are not stuck
with their atoms but are free in the cloud;
plasma naturally occurs in flames,
lightning, and auroras.

31. BOSE-EINSTEIN CONDENSATE
is a state of matter which forms when particles (bosons) are
cooled to almost absolute zero.
• referred to as the 'fifth state of
matter
• they are super unexcited and super
cold atoms.
• this was finally observed in 1995
when rubidium-87 atoms were
cooled to 170 nanokelvins

32. Satyendra Nath Bose – Indian physicist, who also discovered
the subatomic particle, the boson.
• Sent his ideas to Albert Einstein
• July 2018, ISS cooled a cloud of rubidium atoms to
ten-millionth of degree above absolute zero

33. • All matter can undergo physical and chemical changes.
CHANGES OF MATTER
PHYSICAL CHANGE – occurs when a substance
alters its state (phase change), but does not change its
chemical composition – E.g. grinding, cutting
Physical changes can be classified as reversible or
irreversible.

34. PHASE CHANGE – the transition of a substance from
one state to another – Depends on temperature and
pressure.
Affects:
Particle arrangement, the energy of particles, the distance
between particles
Either:
Exothermic – heat is given off i.e. Removal of energy
Endothermic – absorption of heat i.e. Input of energy

35. Changes of State:
Solid to Liquid
M E L T I N G

36. Changes of State:
Liquid to Solid
F R E E Z I N G

37. Changes of State:
Liquid to Gas
E V A P O R A T I O N

38. Changes of State:
Gas to Liquid
C O N D E N S A T I O N

39. Changes of State:
Solid to Gas
S U B L I M A T I O N

40. CHEMICAL CHANGE – occurs when a substance is
converted into a new or different substance
• Also referred to as a chemical reaction
The chemical reaction consists of reactants and products
reactants – starting substances
products – substances that are formed/produced

41. Classify each as a physical or chemical change:
1. A dead fish rotting Chemical change
2. Dissolving salt in water Physical change
3. Boiling salt water until
only salt remains
Physical change
4. Melting steel Physical change
5. Bending steel Physical change
6. Cracking ice Physical change

42. Identify the following as physical or a chemical change:
1. Sugar ferments to form alcohol Chemical change
2. Gallium metal melts in your hand. Physical change
3. Platinum reacts with hydrogen
peroxide at room temperature.
Chemical change
4. Leaves turn color in the Fall. Physical change
5. Milk turns sour. Chemical change
6. Wax is melted over a flame and
then catches fire and burns.
Chemical change

43. • Matter can be classified or identified as either pure
substances or mixtures
CLASSIFICATION OF MATTER
• Substance – kind of matter that cannot be separated
by any physical process
• Pure substances are considered as either elements
or compounds

44. – a substance that cannot be broken down
into simpler substance by physical and
chemical reaction
ELEMENTS
• Consists only of one kind of atom
• Building blocks for other substances
• Are organized on the periodic table, based on their
properties
– Consists of name and symbol
– 92 naturally occurring elements, 26 synthesized
– E.g. Fe, Cu, Ag, Si, etc.

46. The periodic table of elements is a table that arranges the
chemical elements in a logical way. They are arranged based
on their atomic number, electron configurations, and chemical
properties. The rows of the periodic table are called periods.
The columns are called groups.

47. In 2016, four new elements
were added to the periodic
table.

48. - a substance that consists of two or
more elements chemically bonded
COMPOUNDS
• A compound is always composed of the same elements,
in the same proportion by mass
• Most of the matter in the universe exists as compounds

49. • Compounds can be synthesized or decomposed
 Synthesis - combination of elements to form
compounds. Ex.
Decomposition - splitting of compounds into their
individual elements. Ex.

50. – combination of two or more substances in
which each substance retains its individual
properties
MIXTURES
• Therefore, substances ARE NOT chemically combined, just
mixed physically
• Can be separated by physical methods
• Classified as:
 Homogeneous
 Heterogeneous

51. • mixture where the composition
of the substances are constant
throughout
Homogeneous Mixture
• individual substances are
indistinguishable

52. Also referred to as solutions – a mixture of solute and
solvent
Solute - substance in a smaller amount, which is
dissolved in the solvent
Solvent - the liquid in which the solution is made of
and is in a greater amount.

54. • mixture where the individual
substances remain distinct
Heterogeneous Mixture
• individual components can be
distinguished
• can easily be separated by
physical methods

55. Identify the following as homogeneous or heterogeneous
Heterogeneous Homogeneous

56. Identify the following as homogeneous or heterogeneous
Heterogeneous Heterogeneous

57. Identify the following as homogeneous or heterogeneous
Heterogeneous Homogeneous

58. Identify the following as homogeneous or heterogeneous
Homogeneous Homogeneous