Coulombunit of chargeJ.J. Thomson (1897)discovered the electronHenri Becquereldiscovered radioactivity in 1896Marie CurieA Polish physicist who, with French husband Pierre, discovered radium emits subatomic particlesRobert Millikan1909 oil drop experiment, calculated the charge of the electron, calculate the mass of electronsErnst RutherfordDiscovered the nucleus in 1909. Developed the nuclear theory of the atom.Neils Bohr (1913)- he describes the atom as small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus
- this is similar in structure to the solar system, but with electrostatic forces providing attraction rather than gravityWhere are protons located?nucleusWhere are neutrons located?nucleusWhere are electrons located?shellProton charge+1electron charge-1neutron charge0Example of molecular formulaC6H12O6Example of structural formulaH-O-O-HExample of ball and stick modelO———-O
\
O———O
I
OExample of a space-filling modelIt looks like blobs melted together or like a ballon animalIonsAre formed by the loss of gain of electrons there by becoming either a + or - charged particleCationspositively charged ionsAnionsnegatively charged ionsThe periodic table was developed byMendeleev
