Life's Chemical Basis Flashcards
matter
takes up space and has mass
basic ingredient of matter
element
element
substance that cannot be
broken down into other substances by chemical reactions (cannot be chemically broken down.) Found on periodic table.
compound
Two or more elements
4 most important elements (96% of living matter):
C, O, H, N (in order of amount)
Atom
smallest unit of an element
parts of atom
neutron, proton, electron
neutron
neutral charge, found in nucleus,
proton
positive charge, found in nucleus,
electron
negative charge, moves rapidly around the nucleus
valence shell
outermost shell of atom
What determines the reactivity of the atom with other atoms?
Number of electrons in valence shell
When will an atom be unreactive or reactive?
Unreactive if shell is full and vv
full valence shell
full=8 electrons
Chemical bonds
form when atoms with
incomplete valence shells interact to produce complete valence shells
Chemical reactions
break or form chemical bonds to
change reactants into products
law of conservation of matter
cannot be created or destroyed
What happens to matter during a reaction bc of the law of CoM?
conserved
Are chemical reactions reversible?
Most
When is chemical equilibrium reached?
when the forward and backward
reaction rates are equal
types of bonds
ionic, covalent (nonpolar and polar)
Ionic bonds-
form when electrons are
transferred from one atom to the other
ions
Resulting atoms of ionic bonds are called ions, and positive and
negative charges of ions?
(ion–charged atom/s)
covalent bonds
electrons are shared, occurs between two
atoms of
similar pulls on electrons