Atoms, Ions, Molecules Flashcards
Who first discovered atoms?
Democritus
Who opposed Democritus idea of atoms?
Aristotle
What two laws did John Dalton proposed?
Law of Conservation of Mass
Law of Constant Composition
State the Atomic Theory
- Matter consists of tiny, indivisible particles called atoms
- All atoms of a given element are identical. Atoms of different elements differ in mass.
- Compounds are formed when atoms different elements combine in a fixed ratio.
- Chemical reaction involves only reorganization of atoms. Atoms cannot be created or destroyed.
What is the atomic model of Dalton?
Billiard Ball Model
Who discovered the electrons?
J.J Thomson
What experiment did J.J Thomson conduct?
Cathode Ray Tube
What is the Atomic Model name of J.J Thomson?
Plum Pudding Model
Who discovered proton?
Eugen Goldstein
What did Eugen Goldstein do that is different from J.J Thomson?
He filled the Cathode Ray Tube with Hydrogen
Who discovered the nucleus of the atom?
Ernest Rutherford
What experiment did Rutherford conduct?
Gold Foil Experiment
What is the name of Rutherford’s atomic model?
Nuclear Model
What has negligible mass?
electron
Who discovered neutron?
James Chadwick
What is the name of James Chadwick experiment?
Quest for the “Mysterious” particle
What particles make up the mass of the atom?
Protons and neutrons
What determines the atomic number of the atom?
Protons and electrons
Collective mass of the particles in the nucleus
Atomic Mass
Representative of the sum of the number of protons and neutrons
Mass Number
Representative of the sum of the protons and neutrons
Mass Number
Who discovered isotopes?
Frederick Soddy
electrically neutral
atoms
atoms of the same element but different mass number
Isotopes
