Ancient Atoms
Aristotle argued that all substances were built from these 4 elements.
Earth, air, fire and water
He developed the first atomic theory
Who is John Dalton
The number of protons in an atom
What is an Atomic number
This means repeating
What is Periodic
This group consists of shiny, malleable metals and are the most reactive group
What is Alkali Metals
The Greek Philosopher who called the smallest, uncuttable piece of matter, "atomos."
Who is Democritus
Matter cannot be created or destroyed, but it can change forms
What is the Law of Conversation of Mass
The sum of the protons and neutrons in the nucleus of an atom
What is mass number
He was a teacher of chemistry and found a way of organizing 63 known elements for a textbook he was writing.
Who is Mendeleev
This group is not classified as a metal but as a metalloid
What is the boron group
A Greek philosopher who rejected the idea of an atom
Who is Aristotle
Samples of a pure compound always have the same elements in the same mass proportion
What is the Law of Constant Composition
Atoms of an element with the same number of protons but different number of neutrons
What is Isotopes
The columns of a period table
What is groups
This group contains an element that is required for life. All the reactions that occur in your body are controlled by compounds containing this group
What is the carbon group
The history of the atom began around this time?
400 B.C.
This scientist conducted some experiments with gas tubes and electric currents to learn more about atoms
Who is J.J. Thomson
A region of space around the nucleus where electrons are most likely to be found
What is Orbitals
The rows of a periodic table
What is periods
This group has elements that are used in fertilizers and explosives.
What is the Nitrogen group
Meaning, uncuttable or indivisible
Atomos
New Zealand Physicist who researched the atom and radioactivity. He also names the positive charge in the nucleus.
Who is Ernest Rutherford
Electrons that are in the highest energy level (the energy level farthest from the nucleus) of an atom of an element
What is Valence electrons
The number of elements in a modern periodic table
What is 118
This group has an element most common in the earth's crust and reacts with just about anything to form new compounds.
What is the oxygen group