Atomic Theoryists Flashcards
What did Democritus say(4)
•atoms are small, hard particles. • uncuttable• constantly moving• atoms are made up of a single material and form into different shapes and sizes
When was dalton
1803
What did dalton say(7)
•atoms of different elements are different• combined elements• atoms of the same element are exactly alike.• all substances made of atoms. • elements combine in specific proportions. • atoms can’t be created, divided, or destroyed
When was Thomson
1897
What did Thomson say(6)
• negatively charged particles in atoms. • cathode ray tube experiment.• plum pudding model• he called negatively charged particles corpuscles• he didn’t know where negative or positive charged particles were so he called it plum pudding• atoms can be divided into smaller pieces
When was Rutherford
1911
Rutherford(7)
•gold foil• results of gold foil show that plum pudding isn’t accurate• nucleus• most of atoms mass is the nucleus• atoms contain mostly empty space• electrons move in empty space• nucleus is at center of atom and surrounded by empty space
When was Bohr
1913
Bohr(3)
• electrons jump between levels from path to path• electrons travel in different paths •electron paths are found in levels at certain distances from nucleus;no path between levels
When was Schrodinger/ Heisenberg
1926
Schrodinger/ Heisenberg
• electron paths can’t be predicted• electrons are found in electron clouds, not paths• electron clouds are related to the paths in bohrs model• electron clouds are certain regions inside atoms where electrons can be found
When was Democritus
440 BC