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Chemistry - Coggle Diagram
Chemistry
History
JJ Thompson
Found the electrons
"Plum Pudding" Model
Consisted of a uniform sphere of positive charge with negative electrons embedded in the sphere
Robert Milikan
Determined the mass of a single electron through oil drop experiment
James Chadwick
Found the electrons
Ernest Rutherford
Did gold foil experiment
Nucleus is the center of an atom which is very tiny and dense
Found massive area in the center of an atom
Democritis
Atoms are "indivisible"
John Dalton
Atoms are in everything
Atoms of the same elements are identical
Atoms can combine with other atoms in simple ratios
Chemical reactions rearrange the atoms but don't change their identities
Terms
Fission
A nuclear reaction in which a massive nucleus splits into smaller nuclei and simultaneously releases energy
Fusion
Creation of energy by joining the nuclei of two hydrogen atoms to make helium
Half-Life
The time required for one half of the atoms of a radioisotope to emit radiation and decay products
Isotope
Atoms of the same element that differ in their numbers of neutrons
Average Atomic Mass
The weighted average of atomic masses of the naturally occurring isotopes of an element
Atomic Mass Unit
Defined as a mass equal to 1/12 of the mass of the atom carbon-12
Laws
Law of Definite Proportion
States that a given chemical compound always contains the same elements in the exact same proportions by mass
Law of Conservation of Mass
Matter cannot be made or destroyed
Law of Multiple Proportions
States that whenever the same 2 elements form more than 1 compound,, the different masses of one element that combine with the same mass of the other element are in the ratio of whole numbers