Atomic History
Arranged the elements on the periodic table based on atomic mass; first to put together periodic table
Dmitri Mendeleev
Subatomic particle with a positive charge
Proton
Which particles determine the atomic number of an element?
Protons
Atoms of the same element that have different number of neutrons are called:
Isotopes
What is the mass number of Cobalt-59?
59
Gold Foil experiment allowed him to discover that the nucleus was the positively charged center of the atom surrounded by negatively charged electrons
Ernest Rutherford
Subatomic Particle with a negative charge
Electron
How many protons are in an atom of Nitrogen?
7 protons
Two different isotopes of an element have the same number of:
Protons
What is the atomic number of Calcium-40?
20
Discovered Plum Pudding Model; atom is positive sphere with negatively charged particles evenly embedded throughout
JJ Thompson
Subatomic particle with no charge
Neutron
The mass number of an atom is equal to:
Protons + Neutrons
Mg-37
How many neutrons are in an atom of Mg-25?
13
Discovered that electrons travel in fixed orbits around the nucleus of the atom
Neils Bohr
Positively charged center of the atom where most of the mass of the atom is located
Nucleus
How many electrons are in a neutral atom of helium?
2 electrons
Name the two different isotope notations. Give an example of each.
Hyphen form and nuclear form
What is the mass number of an atom that contains 4 protons, 5 neutrons, and 4 electrons?
9
Schrodinger and Heisenberg
The negatively charged area around the nucleus where the volume of the atom is located
Electron cloud
The average of all isotopes of an element is known as the ____________ _____________ ________.
Average atomic mass
What is the most stable isotope of Carbon?
Carbon-12
What is the isotope notation for an atom of Argon containing 22 neutrons?
Argon-40