CHE1501 – GENERAL CHEMISTRY
Chapter 2
Atoms, Molecules, and Ions
,
,2.1 EARLY IDEAS IN ATOMIC THEORY
Atoms were first proposed by Greek philosophers.
• Matter is composed of small finite particles called atomos.
• The term atomos is derived from the Greek word for indivisible.
Elements were first proposed by Aristotle.
• The “elements” were fire, earth, air, and water.
, 2.1 EARLY IDEAS IN ATOMIC THEORY
John Dalton developed modern atomic theory in 1807.
1. Matter is composed of exceedingly small particles called
atoms. An atom is the smallest unit of an element that
can participate in chemical change.
2. An element consists of only one type of atom, which has
a mass that is characteristic of the element and is the
same for all atoms of that element.
3. Atoms of one element differ in properties from atoms of
all other elements.
Chapter 2
Atoms, Molecules, and Ions
,
,2.1 EARLY IDEAS IN ATOMIC THEORY
Atoms were first proposed by Greek philosophers.
• Matter is composed of small finite particles called atomos.
• The term atomos is derived from the Greek word for indivisible.
Elements were first proposed by Aristotle.
• The “elements” were fire, earth, air, and water.
, 2.1 EARLY IDEAS IN ATOMIC THEORY
John Dalton developed modern atomic theory in 1807.
1. Matter is composed of exceedingly small particles called
atoms. An atom is the smallest unit of an element that
can participate in chemical change.
2. An element consists of only one type of atom, which has
a mass that is characteristic of the element and is the
same for all atoms of that element.
3. Atoms of one element differ in properties from atoms of
all other elements.
