Atoms
What is an atom?
The smallest particle that still can be considered an element.
How did atomic theory grow?
Through a series of models that developed from experimental evidence.
What did JJ Thomson discover about the atom?
The electron.
Rutherford's experiment.
What is aimed a beam of positively charged particles at a thin sheet of gold?
What is the outcome of Rutherford's gold foil experiment.
The particles in Rutherford's experiment were expected to pass through the gold film but some of the positive particles were deflected.
What was the major change to Daltons theory?
The knowledge that atoms are made of even smaller parts.
The final results of Rutherford's experiments.
What is the atom is mostly empty space but has a positive charge at its center?
What is the small region at the center of an atom?
The nucleus.
What is the positively charged particles in a atom's nucleus?
Protons.
What model says electrons are found only in specific orbits around the nucleus.
Bohr Model
What model represents electrons that do not orbit the nucleus like planets, instead they move rapidly within a cloudlike region around the nucleus?
Cloud Model
What is the specific amount of energy an electron has?
Energy level
What is the reason atomic theory changed with time?
As more experimental evidence was collected, the atomic theory needed to be revised.
What did James Chadwick discover?
Another particle exists in the nucleus of the atom, the proton.
+1
What is the charge of a proton.
What is the charge of an electron?
The exact opposite charge of the proton.
Why was the neutron difficult to find and it doesn't affect the charge of an atom?
It has no electrical charge.
What is the number of electrons to equal the mass of 1 proton?
1,840
What takes up most of the mass in an atom?
Protons and neutrons in the nucleus.
What is the atomic number?
The number of protons in the nucleus.
Atoms with the same number of protons and different numbers of neutrons.
What is an isotope?
What is the relationship between an energy level and the electron cloud?
Electrons move about within an energy level in an ever-changing path in the electron cloud.
The sum of the protons and neutrons in an atom.
What is the mass number?
What does the number of protons in an atom tell you?
The identity of an element.