A.P. Chapter One Outline
The Nature of Chemistry
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Chemistry is the science of matter and its transformations from one form to
another
Matter is anything that has mass and takes up space
I.
Scientific Methods
 Hypothesis: an idea that is tentatively proposed as an explanation for
some observation and provides a basis for experimentation
 Observations: something that can be directly perceived through ones
senses.
A qualitative observation can not be measured numerically
A quantitative observation can be measured numerically
II.
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III.
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IV.
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V.
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VI.
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Identifying Matter: Physical Properties
Physical properties can be observed and measured without changing the
composition of a substance. Examples include temperature, mass, density,
etc.
Density is the ratio of an objects mass to its volume; D = m/v
Chemical Properties
A substances chemical properties describe the kinds of chemical reactions the
substance can undergo
Chemical reactions are usually accompanied by transfers of energy
Substance and Mixtures
A heterogeneous mixture is one in which properties in one region are different
from properties in another region
A homogeneous mixture, or a solution, is completely uniform and consists of
two or more substances in the same phase
Elements and Compounds
Elements are composed of only one kind of atom and cannot be decomposed
into two or more substances
Compounds are two or more elements chemically combined and can be
decomposed
States of Matter: Solids, Liquids, and Gases
Solids: have rigid shapes, fixed volume, and is relatively incompressible
Liquids: has a fixed volume but indefinite shape; is relatively incompressible
Gases: have neither a rigid shape or fixed volume
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VII.
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VIII.
The kinetic-molecular theory states that all matter consists of extremely
small particles that are in constant motion. The higher the temperature the
greater the speed of the particles
The Atomic Theory
An atom is the smallest particle of an element that embodies the chemical
properties of an element
The law of conservation of mass states that there is no detectable change in
mass during an ordinary chemical reaction
The law of constant composition states that a chemical compound always
contains the same elements in the same proportions by mass
The Modern Atomic Theory
1.
All matter is composed of atoms, which are extremely tiny
2.
All atoms of a given element have the same chemical properties
3.
Compounds are formed by the chemical combination of two or
more different kinds of atoms
4.
A chemical reaction involves joining, separating, or rearranging
atoms
The Chemical Elements
 Every element has been given a unique name and symbol. The
first letter is capitalized, and if there is a second letter it is in
lowercase
 Most elements are metals (they conduct heat and electricity, are
lustrous, ductile, and malleable)
 A molecule is a unit of matter in which two or more atoms are
chemically bonded together
 Allotropes: different forms of the same element in the same
physical state at the same temperature and pressure