Atomic Theory
This law states that mass is neither created nor destroyed during ordinary chemical reactions or physical changes
law of conservation of mass
What two regions make up all atoms?
the nucleus (containing protons and neutrons) and the electron cloud (where electrons orbit around the nucleus)
lowest energy state of an atom
ground state
The arrangement of electrons in an atom is known as the atom’s
electron configuration
defined as a standard scientific unit for measuring large quantities of very small entities such as atoms, molecules, or other specified particles of an element (abbreviated as mol)
mole
The fact that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound is known as the
law of definite proportions
What number uniquely identifies an element?
atomic number
state in which an atom has a higher potential energy than it has in its ground state
excited state
a three-dimensional region around the nucleus that indicates the probable location of an electron
orbital
"carbon-12" is an example of what kind of notation?
hyphen notation
If two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers. This is known as which law?
law of multiple proportions
6.022 × 1023—is the number of particles in exactly one mole of a pure substance - what is the name of this number?
Avogadro's number
mathematically describes the wave properties of electrons and other very small particles
quantum theory
electrons occupy which energy level first? lowest-energy orbitals or highest-energy orbitals
lowest-energy levels fill up first
The following is an example of what kind of notation?
235U
nuclear notation
Who proposed the atomic theory?
John Dalton
short-range proton- neutron, proton-proton, and neutron-neutron forces hold the nuclear particles together and are referred to as
nuclear forces
____________ numbers specify the properties of atomic orbitals and the properties of electrons in orbitals
quantum
a set of eight electrons in the outermost electron shell of an atom
octet of electrons
According to the law of conservation of mass, if element A has an atomic mass of 2 mass units and element B has an atomic mass of 3 mass units, what mass would be expected for compound A2B3?
13 mass units
According to the law of conservation of mass, if element A has an atomic mass of 2 mass units and element B has an atomic mass of 3 mass units, what mass would be expected for compound AB?
5 mass units
The radii of atoms are expressed in what unit?
picometers
this principle states that it is impossible to determine simultaneously both the position and velocity of an electron or any other particle
Heisenberg uncertainty principle
Name the three ways to indicate electron configuration.
orbital notation, electron-configuration notation, noble-gas notation
List the colors of light in the visible spectrum in order of increasing frequency.
The colors of light in the visible spectrum in order of increasing frequency are: red, orange, yellow, green, blue, indigo, and violet