Atomic theory
Who discover the Electrons?
J.J. Thomson
What’s the center part of the atom called?
Nucleus
What does Rn stand for?
Radon
Who came up with the plum pudding model?
J.J. Thomson
What are the three main subatomic particles?
Protons, neutrons, electrons
What did Dalton discover?
The atomic theory
What surrounds the nucleus of the atom?
Electrons
What does the atomic number represent?
Number of protons in the nucleus
What model had a dense nucleus in the middle?
Rutherford’s nuclear model
What is the charge of a proton?
Positive
What part of Dalton’s idea ended up being wrong?
He said all atoms of an element are identical
What tells you what element an atom is?
The number of protons
What is a group or family on the periodic table?
A vertical column of elements with similar properties
What was special about Bohr’s model?
Electrons orbit the nucleus in fixed paths
Where are neutrons found in an atom?
In the nucleus
What experiment used gold foil and surprised everyone?
Rutherford’s gold foil experiment
What are atoms called when they have the same protons but different neutrons?
Isotopes
Who created the first version of the periodic table?
Dmitri Mendeleev
What’s the main difference between Bohr’s model and the quantum model?
The quantum model uses electron clouds and probabilities instead of fixed paths
Which particle controls how atoms react with each other?
Electrons
What did Bohr add to Rutherford’s model to make it better?
Bohr said electrons move in energy levels
What do we call an atom that gains or loses electrons?
An ion
What trend increases across a period and decreases down a group?
Electronegativity
What did Schrödinger use to figure out where electrons might be?
Schrödinger used math equations
How does an electron compare in size and charge to a proton?
Electrons are much smaller in mass and have a negative charge