Chapter 1,2 : Elements of the Periodic Table, Atomic Structure Flashcards
Robert Boyle element definition
An element is a substance that cannot be broken down chemically into simpler materials
Define law of conservation of mass
The law of conservation of mass states that matter is neither created or destroyed in the course of a chemical reaction
Atomic Number who
Moseley, x rays
Triads
Dobereiner, similar chemical properties, atomic weight of middle element midway between the other two
Law of Octaves
Newlands, order of atomic weight
Predicted modern periodic table
Mendeleev
Cathode Rays
Crookes, discharge tube
Electron (Charge to mass (e/m))
JJ Thomson, cathode rays were deflected in a magnetic field. Negative charge
Name electron
Stoney
Charge on electron
Millikan, oil drop experiment
Plum pudding model
Thomson
Nucleus
Rutherford, gold foil
Energy levels who
Bohr
Neutrons
Chadwick, bombarded berrylium
Atomic number definition
The atomic number of an element is the number of protons in the nucleus of an atom of that element
Mass number definition
The mass number of an element is the sum of the number of protons and the number of neutrons in the nucleus of an atom if that element
Isotopes
Isotopes are atoms with the same number of protons but different numbers of neutrons
Relative atomic mass definition
The relative atomic mass of an element is the average mass of an atom of the element relative to one twelfth the mass of an atom of carbon12
Principle of mass spectrometer
Positively charged ions are separated on the basis of their relative masses when moving in an electric field
Processes in a mass spectrometer
Vaporisation
Ionisation
Acceleration
Separation
Detection
