What is Chemistry?
• Definition: Chemistry is the study of
matter, its properties, how and why
substances combine or separate to
form other substances, and how
substances interact with energy.
• Importance: Chemistry is often called
the central science because it bridges
other natural sciences, including
physics, geology, and biology. It helps
us understand the composition,
structure, and changes of matter.
Matter and Its
Properties
• Definition of Matter: Matter is anything that
has mass and takes up space.
• Examples: Solids (ice), liquids (water), gases
(oxygen).
• Properties:
• Physical Properties: Characteristics that can
be observed or measured without changing
the substance’s chemical identity (e.g.,
color, density, volume, mass, boiling point).
• Chemical Properties: Characteristics that
determine how a substance can change into
a different substance (e.g., reactivity with
acid, flammability).
States of Matter
Liquid: Has a definite
Solid: Has a definite
volume but takes the Gas: Has neither a
shape and volume.
shape of its container. definite shape nor
Particles are tightly
Particles are close volume. Particles are far
packed and only vibrate
together but can move apart and move freely.
in place.
past one another.
Chemical vs. Physical Changes
Physical Change: A change in Chemical Change: A change
which the form of matter is that results in the formation of
altered but one substance is one or more new substances
not transformed into another with new chemical and
(e.g., melting ice, tearing physical properties (e.g.,
paper). rusting iron, burning wood).
The Scientific Method
STEPS: OBSERVATION: HYPOTHESIS: EXPERIMENT: ANALYSIS: CONCLUSION: IMPORTANCE: THE
GATHERING DATA FORMULATING A TESTING THE INTERPRETING THE DRAWING SCIENTIFIC METHOD
AND NOTICING TENTATIVE HYPOTHESIS DATA AND RESULTS. CONCLUSIONS AND IS ESSENTIAL FOR
PHENOMENA. EXPLANATION OR THROUGH REFINING THE CONDUCTING
PREDICTION. CONTROLLED HYPOTHESIS IF SYSTEMATIC AND
EXPERIMENTS. NECESSARY. REPRODUCIBLE
RESEARCH.
Branches of Chemistry
Organic Chemistry: The study of carbon-containing compounds and their properties.
Inorganic Chemistry: The study of inorganic compounds, typically those that do not contain carbon-hydrogen bonds.
Physical Chemistry: The study of the physical properties and behavior of matter, and the changes it undergoes during
chemical reactions.
Analytical Chemistry: The study of the composition of substances and the development of tools used to measure properties
of matter.
Biochemistry: The study of chemical processes within and related to living organisms.
Applications of Chemistry
• Everyday Life: Chemistry is involved in cooking
(chemical reactions in food), cleaning (detergents and
soaps), and medicine (pharmaceuticals and vaccines).
• Industry: Chemistry is crucial in manufacturing
(plastics, metals), energy production (batteries, fuels),
and materials science (developing new materials).
• Environment: Chemistry helps in understanding and
addressing pollution, developing sustainable
practices, and creating green technologies.
Summary
• Key Points:
• Chemistry is the study of matter and its interactions.
• Matter has physical and chemical properties and exists in different states.
• Physical and chemical changes are fundamental concepts in chemistry.
• The scientific method is a systematic approach to research.
• Chemistry has various branches and numerous applications in everyday life, industry, and the
environment.
• Importance of Chemistry: Emphasize how chemistry helps us understand the world and improve our
quality of life.
