History of the Atom
He believed that all substances were built from only four elements: air, fire, earth, and water.
Who is Aristotle?
This term represents the number of protons in an atom
What is the atomic number?
This subatomic particle has a positive charge.
What is the proton?
This is the number of protons in an atom of carbon (which has an atomic number of 6).
What is 6?
He was the first person to say that matter was made up of atoms. He said that atoms of different things (like water, rocks, etc.) differ in size and shape.
Who is Democritus?
This term refers to the sum of the protons and neutrons in the nucleus of an atom.
What is the mass number?
This subatomic particle orbits the nucleus.
What is the electron?
This is the mass number of an isotope of Beryllium with 4 protons and 5 neutrons.
What is 9?
His theory stated that all matter is made up of atoms, that all elements of an atom are identical in mass and properties, that compounds are made of atoms from more than one element, and that in specific compounds the atoms of elements always combine in the same ways.
Who is John Dalton?
This law says that matter cannot be created or destroyed but it can change forms.
What is the Law of Conservation of Mass?
This subatomic particle has no charge.
What is the neutron?
This is the number of electrons in an atom of carbon-13 (which has a mass number of 13 and has 6 protons).
What is 6?
He developed the idea of the electron and said that atoms are spheres of positive charge with a few negatively charged electrons spread throughout the atom (like raisins in plum pudding).
Who is J. J. Thomson?
This term refers to atoms of an element with the same number of protons but different numbers of neutrons.
What are isotopes?
This is the smallest subatomic particle.
What is the electron?
This is the number of neutrons in an atom of carbon-13 (which has a mass number of 13 and has 6 protons).
What is 7?
He developed the model that showed atoms were made of a small, dense positively-charged nucleus with negatively charged electrons orbiting the central nucleus.
Who is Ernest Rutherford?
This law says that samples of a pure compound always have the same elements in the same mass proportion.
What is the Law of Constant Composition?
This is where most of the mass of an atom is located.
What is the nucleus?
This is the number of neutrons in an isotope of Chlorine that has an atomic number of 17 and a mass number of 35.
What is 18?