All matter is made of tiny particles called atoms'

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All matter is made of tiny particles called atoms.
Atoms are the building blocks for all substances.
In an element, all the atoms are the same kind.
O is the symbol for oxygen
H is the symbol for hydrogen
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Sometimes atoms combine with each other to form
molecules.
A molecule is a group of chemically combined
atoms. Molecules may have 2 atoms or they may
have hundreds of atoms.
Example
O2 is an oxygen molecule because it has 2 oxygen
atoms.
A Compound is a molecule.
Example
H2O, compound, more than 2 elements.
hydrogen
oxygen
but in compounds there are more than one type
of atom or more than one element.
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Elements, Compounds, and Mixtures I. Element
consists of only one kind of atom
cannot be broken down into a simpler type of
matter by either physical or chemical means
can exist as either atoms OR
ex argon -Ar
molecules
ex nitrogen N2
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A. Atomic Symbol is derived from the first
letters of the elements name Ex.
Carbon C , Oxygen - O sometimes in
Latin Ex. Gold Au (aurum), Lead Pb
(plumbum) Only first letter is capitalized Co
is cobalt but CO is carbon monoxide (carbon and
oxygen combined)
B. Elemental Formula tells you how many atoms
are grouped in an element by using a
subscript Ex. Sulfur groups together in
eights so it is written S8
Nitrogen and Oxygen come in pairs and is
written N2 and O2
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II. Compounds are formed when atoms of
different elements attach to one
another. Sodium (Na) and Chlorine
(Cl) attach together to make NaCl table
salt Iron (Fe) and Oxygen (O) combine to
make Fe2O3 iron oxide (rust)
Ex Water - Oxygen (red) and hydrogen (white)
A. Chemical Formula a symbol representing
a compound. Ex H2O water, NaCl table
salt, Fe2O3 iron oxide (rust)
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B. Compounds have different physical and
chemical properties than the elements they are
made of. Ex Sodium (Na) soft silvery
metal melting point 97.50 C, reacts violently
with water Chlorine (Cl)
very toxic, boiling point - 340 C, gas is
yellow-green Together Sodium
Chloride (NaCl) table salt, translucent,
brittle, colorless crystal, melts at 8000 C
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III. Mixtures most materials are mixtures A.
of two or more elements Stainless steel is
iron (Fe), chromium (Cr), nickel (Ni), and
carbon (C) B. of two or more compounds
Sparkling mineral water water (H2O),
mineral salts (Na2 CO3 Na HCO3 2H2O), and
carbon dioxide gas (CO2) C. of elements and
compounds Our atmosphere nitrogen (N),
oxygen (O), Argon (Ar), and carbon dioxide
(CO2), water vapor (H2O) Mixtures can be
separated by physical means. Ex. Distillation
water evaporates from seawater and leaves
salt.
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Classification of Matter Pure made of a single
element (gold) or a single compound
(Salt-NaCl) Impure means a mixture of
elements or a mixture of compounds Most
substances are mixtures and it is almost
impossible to be pure.
Heterogeneous Mixture different components can
be seen as individual substances
Ex pulp in orange juice, sand in water, oil on
water
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Homogeneous Mixture - have the same
composition throughout (one portion of the
mixture has the same ratio of substances as
does any other portion) Solution all
components are of the same phase ex air
(N2, O2), Salt Water (NaCl, H2O), White Gold
(Au, Pd) Suspension components are of a
different phase ex milk (water, solid
proteins) blood (water, solid
proteins) fog (air, tiny water droplets)
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Centrifuge - a devise that can separate the
components of a suspension but not a solution.
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Subatomic particle particles smaller the atom
and is contained inside the atom. Nucleus
center or core of the atom. Contains 99.9 of
the mass of the atom. Proton positively charged
subatomic particle found in the nucleus of the
atom