Atomic Structure
What is the center of the atom called?
Nucleus
What was the first model of the atom called?
The plum pudding model?
What is a group on the periodic table?
A vertical column
What is the name of group 1 on the periodic table?
Alkali metals
What is the atomic number?
The number of protons
What two particles are in the nucleus?
Protons and neutrons
What discovery about the behavior of electrons led to the current atomic model?
Electrons behave like both waves and particles
What is a period on the periodic table?
A horizontal row
Give an example of an element that is a transition metal
Anything in groups 3-12
How do you calculate the number of neutrons when you are given atomic mass and atomic number?
Atomic mass - atomic number
Where are electrons located?
In the electron cloud
What was the first periodic table organized by? Who created it?
Atomic mass
Dmitri Mendeleev
How do we know how many valence electrons are in an element?
By using the group number - 10
(except for groups 1-2)
Give an example of an element that is a halogen
F, Cl, Br, I, At
How do you calculate the average atomic mass on the periodic table?
You multiply all the isotopes by their percent abundance and then add them up
Name all three subatomic particles and their charges
Proton - positive
Electron - negative
Proton - neutron/no charge
Who discovered electrons? How?
JJ Thompson
Using a cathode ray tube
Give me the name and atomic mass of the element with an atomic number of 8
Oxygen
15.99 or 16
Which group on the periodic table is made up of unreactive gases?
Noble gases
How many neutrons does Iron-60 have?
60 - 26 = 34
34 neutrons
What is an isotope?
An atom with a different number of neutrons
Who discovered the nucleus? How?
Rutherford
Using the gold foil experiment
How is the modern periodic table organized? Who created it?
It is organized by atomic number
Created by Henry Moseley
What is the name of the group on the periodic table that is radioactive?
Actinides
An element has 3 isotopes:
The first isotope has a mass of 127 and occurs 80% of the time
The second isotope has a mass of 126 and occurs 17% of the time
The third isotope has a mass of 128 and occurs 3% of the time
What is the average atomic mass? Based on that, what is the element?
(127 x .80) + (126 x .17) + (128 x 0.03) = 126.86
Iodine