Atomic Theory
What is the basic unit of matter called?
Atom
Where are the neutrons located in an atom?
Inside the nucleus.
What subatomic particle orbits the nucleus?
Electrons
How many electrons are in potassium?
19
What Greek philosopher proposed the first atomic theory?
Democritus
How do you find the number of neutrons in an atom?
Mass # - # of protons (or atomic #)
What do the circles represent in a Bohr's diagram?
energy levels/shells/where electrons normally are
How many neutrons are in the Carbon - 16 isotope?
10
Which scientist's atomic model represents how planets orbit the sun?
Niels Bohr
Which subatomic particles weigh 1u (or have relative mass)?
Protons, neutrons
What is the name of the most modern and up-to-date model of the atom?
Electron Wave Model
If the atomic number of an atom is 84 and it has 39 neutrons, what is it's mass number?
123
Which scientist is known for discovering the electron?
J.J. Thomson
What is an isotope?
The same element with a different number of neutrons.
How many electrons can fit in the 4th energy level?
32
How many valence electrons does magnesium have?
2
Which scientist is known for creating the solid sphere atomic theory?
John Dalton
What is the charge of a neutron?
0 (neutral)
What happens to an electron when it absorbs energy in a Bohr model?
moves to a higher energy level
How many energy levels does selenium use?
4 (has 6 valence electrons)