Unit 3 Review Guide
I. Review on the 10 Scientists and their contribution to the atomic theory
Development of the Atomic Theory

Which scientist is responsible for:
o
Developing the planetary model of the atom based on quantum energy levels
o
Alpha particles, positive charge with a mass 7500 x of electron. Proved the plum pudding
model wrong. Nucleus center (+) and tiny electron moved in space around it.
o
Discovered the electron and developed the plum pudding model of the atom
o
Stated that electrons behave like waves
o
Developed the first atomic theory of matter
o
Oil drop experiment: disovered that atoms had positive and negative charges and they equal
each other
o
Wave Mechanical Model or Quantum Mechanical Model. Furthered De Broglie’s idea of
wave by stating that electrons are in clouds but in certain energy level.
II. Atomic Structure
Subatomic Particles
Mass
Charge
Proton
Neutron
Electron




For each of the following elements, determine the number of protons:
o
Fluorine _________________
o
Iron _________________
For each of the following elements, determine the atomic number of:
o
Silicon _________________
o
Potassium _________________
For each of the following elements, determine the number of electrons:
o
Oxygen _________________
o
Boron _________________
For each of the following elements, determine the number of neutrons:
o
Arsenic _________________
o
Sulfur _________________
Where it is found?

How many protons, electrons, and neutrons respectively does 186
74 W have?

How many protons, electrons, and neutrons, respectively, does
60
28
Ni have?

How many protons, electrons and neutrons, respectively, does
70
31
Ga3 + have?

The number of neutrons in one atom of

240
U is ________________________
92
Mass number of an element represents the number of _______________ + _______________.

An atom with 30 protons and 31 neutrons is an atom of ___________. (chemical identity)

Atoms of the same element having the same atomic number but different mass numbers
are called _________________________________.
o The atom with 80 neutrons and 60 protons has a mass number of ______________.

How many electrons are present in an iron atom with a mass number of 56?

Write the complete symbol of an atom that has 47 protons, 47electrons, and 61 neutrons

The number of protons in the nucleus of an atom is called its
a.
mass number
b.
valence
c.
isotope number
d.
atomic number
e.
none of these
o
If an atom has 55 protons, 78 neutrons, 55 electrons, its complete chemical symbol would be
o
If an atom has 28 protons, 31 neutrons, 28 electrons, its complete chemical symbol would be
o When an electron in the ground state absorbs energy, it goes to a(n) ______________
state.
Electron Configuration and Orbital Diagram

Write the long hand Electron Configurations of these elements:
o
Mg _________________________
o Fe _________________________

Write the Short Hand Electron Configuration of these elements:
o Xe : _____________________________
o Se: ______________________________

Which element has the following electron configuration:
o 1s 22s 22p 63s 23p 3

o 1s 22s 22p 63s 23p 64s 23d 5
Draw the orbital diagram of the following elements:
o Carbon:
o Fluorine:
Periodic Trends

Define: Ionization Energy _________________________________________________________

Which element has the most ionization energy?


Which element has the least ionization energy?


I, F, Ar, Rb
Define: Electronegativity __________________________________________________________

Which element is the most electronegative?


K, Na, Ne, At
Which element is the least electronegative?


Sc, Ti, Ga, Kr
Co, Fe, W, Xe
Define: Atomic Radius ____________________________________________________________

Which element has the largest atomic radius?


V, Cr, Cu, Ni
Which element has the smallest atomic radius?

Ba, Cs, Pt, Hg