People
Who first used the term atom?
Democritus
What is an atom?
The smallest particle of matter
How many atoms are in a penny?
More than people on earth
Name the 4 forces at work in the nucleus of the atom.
Strong, gravitational, electromagnetic, and weak forces
Do most elements have isotopes?
Yes
Who found the nucleus of the atom?
Rutherford
What does the word atom mean?
Indivisible or uncuttable
What are the positively charged particles of the atom and where are they located?
Protons and in the nucleus
What is a strong force?
Causes protons to push away from each other
What is an isotope?
Atoms with the same number of protons like the element but have different amounts of neutrons.
What did Bohr say the atom model was like?
It look like the planets orbiting the sun.
What model of the atom do we use today?
The Electron Cloud Model
What is a neutron and where do you find them?
A particle with no charge(neutral) found in the nucleus
What is gravitational force?
Pulls the protons and neutrons together to form the nucleus.
What is a radioactive isotope?
Unstable atom whose nucleus pulls apart over time.
What did Thomson find out about an atom?
He found the electron
Where is the nucleus and what makes it up?
It is in the center of the atom and is made of protons and neutrons
Fill in the blank
The smallest particle is the _______ it is charged _______ and __________around the _______ of the atom.
electron negative spins nucleus
What is the electromagnetic force?
This holds the electrons around the nucleus.
What is an atom that has become charged?
An Ion
What are the 3 parts of Dalton’s Theory?
All substances are made up of atoms
Atoms of the same element are all alike
Atoms join with other atoms to make new substances
What is the atomic mass number?
The atomic mass is the number of protons and neutrons
What is the area around the nucleus where the electrons are found called?
Electron Cloud
What is the weak force?
It is found in radioactive elements that allow the nucleus to pull apart.
What is the atomic number?
It is the number of protons in an atom