Unit 1, Chapter 2 Flashcards
(33 cards)
what does science study?
the natural world/physical universe
components of the physical universe include
matter, energy and forces
These are the building blocks of matter
atoms
atoms bond so that they can
become stable
atoms lose their individual identity when chemically bonded to form
molecules
Ionic bonds bond together
cations and anions
These are the two types of covalent bonds
polar and pure
Laws are described a
phenomenon in nature that we always assume is true
These were the only stable atoms when Earth was created
Helium and Hydrogen
John Dalton created this model
Billiard Ball Model
Bohr disproved dalton and created this model
Bohr Model
These are the six essential elements:
C, O, H, N, P, S
Chemical bonds formed from electron transfer
ions
loss of electrons
oxydation
Covalent bonds are
a SHARED PAIR of electrons
As electronegativity increases
the pull of the electron increases
When two atoms have the same electronegativity they are considered to be
nonpolar
When atoms do not have equally shared electrons they are
polar
Dipoles
are partially negative and partially positive charges
Trace Elements
an element that is only needed in very small quantities by an organisms
Two examples of trace elements include
Fe and I
one amu is
1.7 x 10^-24
energy is defined as
the capacity to cause change
the atom who takes the electron is being
reduced