GENERAL
CHEMISTRY
1
Chemistry is the study
of matter and the
changes it undergoes.
Chemistry is branch of natural
science that deals principally with
the properties of substances, the
changes they undergo, and the
natural laws that describe these
changes.
HISTORY OF
CHEMISTRY
ALCHEMY
CHEMISTRY
PLATONIC
SOLIDS
ALCHEMY
CHEMISTRY
Democritus &
Leucippus
Matter could be divided
into tiny particles until
such point where it can
no longer be divided
anymore.
“ATOMOS”

Findings of Joseph Proust (Composition of
Matter)


Proust (1799); proposed about important principle
about quantitative analysis of chemical reactions.
Compound formation; elements always combine in
similar proportions by mass regardless of the size of
the sample (LAW OF DEFINITE PROPORTIONS)

Support Law of Multiple Proportions



if two or more different compounds are composed of
the same two elements, then the ratio of the masses
of the second element combined with a certain mass
of the first element is always a ratio of small whole
numbers.
Carbon monoxide (CO) & Carbon dioxide (CO2)
Fixed C ratio BUT 1:2 O ratio


When reaction is done in a closed container,
the total mass BEFORE and AFTER the
reaction is the same. (LAW OF
CONSERVATION OF MASS)
Mass is neither created nor destroyed
during a chemical reaction.
ASSIGNMENT:
 Research on the different
models of atoms.
Prepare for a quiz next meeting.
Antoine Lavoisier Contributions
• He had proof of Boyle’s concept of a simple substance, now
known as the chemical element.
• A chemical element is a substance that cannot be broken
down into simpler components.
• He defined a compound as a substance composed of these
elements.
• He came up with an initial list of 33 elements, and created a
systematic way of naming elements and the compounds they
created.
• He also wrote the first Chemistry textbook.
• For this and many other contributions, he became known as
the Father of Chemistry.