Chapter Two Flash Cards
Most of the mass of an atom is in the
Nucleus
Most of the volume of an atom is
empty space
Nucleus is surrounded by
Electrons
Neutral atoms have equal numbers of
protons and electrons
Isotope
Type of atom with different masses but chemically indistinguishable to a known element
AMU
atomic mass unit
Mass number is equal to
protons + electrons
For ions, the number of electrons does not equal the number of
protons
law of conservation of matter
atoms are not created or destroyed during a chemical process
Law of definite proportions
All samples of a pure compound contain the same elements in the same proportion by mass
neutrons
uncharged, subatomic particles with a mass approximately the same as that of protons and found in nucleus
Mass number =
Atomic Number + neutrons
Protons + neutrons
Ion Charge
Protons = Electrons
Molecular Formula
indicates the type and number of atoms in a compound
Empirical Formula
Indicates the lowest whole number ration of atoms in a compound
Metals
Shiny, malleable, conduct heat + electricity
Nonmetals
dull, insulate heat + electricity
Metalloids
can have properties of metals and/or nonmetals
Alkali Metals
Group 1 (except hydrogen)
Alkaline Metals
Group 2
Pnictogens
Group 15
Chalcogens
Group 16
Halogens
Group 17
Noble Gases
Group 18
Group 1 during chemical reactions
lose one electron
1+ charge cation
Group 2 during chemical reactions
lose 2 electrons
2+ charge cations
Non-Metals Group 17 During Chemical Change
gain one electron
1- charge anion
Non-Metals Group 16 During Chemical Change
gain two electrons
2- charge anions
Ionic Compound
forms when electrons are transferred through electrostatic attraction
Molecular Compound
Forms when electrons are shared
