Topic 2 - An understanding of the nature of matter has developed through observations over time Flashcards
What is Gold?
Highly valued cause of the properties.
What are properties of gold?
Lustre, colour, lack of tarnishing and softness. The softness made it not difficult to shape into detailed designs, created into wire, and beaten into sheets.
What is copper used in?
Could be used to pots, coins, tools, and jewelry.
Can be rolled into sheets (Malleability) and stretched into wires (Ductility)
What did John Dalton discover?
Discovered the Billiard Ball Model
Said that matter was made up of elements (pure substances which include no other substances)
What did J.J. Thomson discover?
J.J. Thomson: Raisins in A Bun
Discovered a subatomic particle (a particle which is smaller than an atom)
Directed a series of experiments with cathode, ray tubes.
Discovered electrons
He said that an atom included a positively charged sphere in which negatively charged were inserted, like raisins in a bun.
Protons: + Negative - Electrons = neutral
Hantaro Nagaoka
electrons orbited a large central positive mass.
Ernest Rutherford (Saturn)
Shot positively charged particles through thin gold foil.
Introduced the idea of a nucleus. He shot positively charged particles through thin gold foil. Some particles were deflected.
The Bohr’s Model
Electrons are in orbital shells.
James Chadwick
He said that the nucleus was made up of positively charged protons and neutral particles called neutrons.
What is a period?
Horizontal row, numbered 1 to 7 on the Periodic Table.
What is a Group or Family?
it is the vertical row, numbered 1 to 18 on the Periodic Table.
What does Atomic Number mean?
The number of protons in the nucleus of an atom.
It identifies the number of electrons in the atom because all atoms are neutral in charge.
What is Atomic Mass?
The total mass of protons and neutrons in an atom`s nucleus.
What is atomic mass measured by?
It is measured by the atomic mass unit.
What are properties of a metal?
Shiny, Malleable, Ductile, Conducts Electricity
