Lesson 1.3 Flashcards
a kind of matter with a definite or fixed composition
pure substance
Pure substances are classified into elements and compounds
is made up of
one kind of atom, or two or more of the same kind of atoms that are chemically combined.
element i
is made up of different kinds of atoms that are combined
through a chemical reaction
have different properties from the elements that
make them up
a compound
are the simplest substances because they are made up of only one kind of atom.
It is a pure substance that is composed of only one type of atom.
are the simplest substances because they are made up of only one kind of atom.
It is a pure substance that is composed of only one type of atom.
t cannot be decomposed into simpler substances by physical or chemical means.
Thus, it is not possible to alter the identity through ordinary chemical
reactions.
Physical changes such as melting, freezing, or cutting do not change the identity of pure
substances.
simplest forms of substance, they are also considered as the
building blocks of matter
elements
start at the left and make up most of the elements in the periodic table. In fact, all
elements to the left of the staircase-like line in the periodic table (except hydrogen) are
generally classified as
metals
are at the right part of the periodic table and are
often shaded with different colors to distinguish them from metals
nonmetals
between the metals and nonmetals. These elements form the staircase-like line in the
periodic table
metalloid
Metals have properties that distinguish them from nonmetals. For instance, metals (except
mercury) are solid at room temperature. Metals have luster or the property that makes
them shiny.
Most metals exhibit malleability or a property that enables metals to be
hammered into thin sheets without breaking.
Metals also possess ductility or the ability to
be drawn into wires.
This is the
reason why metals are good raw materials for making cooking pans, pots, and electrical
wirings
on the other hand, are the opposite of metals. Generally, nonmetals are either
gaseous or dull solids. These elements are brittle as they break apart easily when subjected
to a heavy blow. Nonmetals are poor conductors of heat and electricit
on the other hand, are the opposite of metals. Generally, nonmetals are either
gaseous or dull solids. These elements are brittle as they break apart easily when subjected
to a heavy blow. Nonmetals are poor conductors of heat and electricit
Nonmetals
nonmetals major elements
in living things
carbon, hydrogen, oxygen, nitrogen, and sulfur
are elements that exhibit properties of both metals and
nonmetals.
some are shiny like metal but are also brittle like a nonmetal
can conduct heat and electricity but not as good as how metals act as
conductors
metalloids/semimetals
semiconductors
are pure substances that are
composed of two or more different elements that
are combined in a fixed ratio by a chemical reaction
Compounds