History
Suggested that elements are made of only one atom.
Dalton
Which subatomic particle has a negative charge?
An electron
In a neutral atom what two things does an element's Atomic Number tell you?
The number of protons and the number of electrons
Carbon is atomic number 6, how many protons does a atom of carbon have.
6 protons
Daily Double - Which type of radioactive decay is used in many smoke detectors?
alpha
Who provided evidence for the existence of the nucleus in an atom?
Ernest Rutherford
Daily Double - Which subatomic particle has a positive charge?
How can you determine the number of these positive charges?
A proton
Atomic Number on the Periodic Table
Daily Double - To find the number of neutrons in an atom, you would do what?
mass number - number of protons
or atomic mass - number of protons
Oxygen is atomic number 8, how many electrons does a neutral oxygen atom have.
8 electrons
Where are electrons found in an atom?
The electron cloud / energy levels
J.J. Thomson's experiments provided evidence that an atom contains...
What is his model called?
contains negatively charged particles called electrons
Plum pudding model
Which subatomic particle has a neutral charge?
A neutron
What is unique for any given element?
The number of protons
Potassium has 19 protons and 20 neutrons, what is its atomic mass?
39 amu
Daily Double- An atom has 8 protons and 10 electrons, does it have a neutral charge. If no, what is its charge?
No, -2
In Niels Bohr's model of the atom, electrons move like what? What is his model called?
The solar system.
Planetary Model
Which particle identifies the element?
Protons
Where is most of the mass of an atom located?
The nucleus
Phosphorus has a atomic mass of 31 amu and an atomic number of 15. How many neutrons does an atom of phosphorus have?
16 neutrons
A Calcium atom has 20 protons and 18 electrons. Does it need more protons or more electrons to become neutral?
more electrons, you cannot change the number of protons
What was the name of the experiment Ernest Rutherford used to discover the nucleus?
What was the name of his model?
The gold foil experiment.
Nuclear Model
True or False? Protons and neutrons have about the same mass.
True
What subatomic particle determines how an atom will bond with other atoms?
electrons
How many protons, neutrons and electrons does an atom of Radon (Rn) have? You may use your periodic table
86 protons, 86 electrons, 136 neutrons
How many electrons are in each energy level for the element Sodium (Na)? How many valence electrons does it have?
1st- 2e
2nd 8e
3rd 1e
It has one valence electron