CEM 151 Lecture Notes - Lecture 4: Cathode Ray Tube, Ernest Rutherford, Henri Becquerel
Document Summary
Theory of atoms- must be some piece of matter that cannot be further divided. John dalton-revived idea and made it science by measuring the atomic weights of 1 elements. All atoms of a given element are identical. The atoms of one element are different from other atoms. Atoms cannot be changed, created or destroyed. Compounds are formed when atoms of more than one element combine (same ratios) Relative amount of each element in a compound doesn"t vary. Streams of negatively charged particles were found to emanate from cathode ray tubes. Either really powerful charge or really small. Vary electric field until the drops float. Vary the charge jono the drop with more x-rays. Set e, measure mass of drop(m) and know g. find q. Types found by ernest rutherford: particles- attracted to negative electrode, positive charge (he nucleus) ) (cid:533) particles- attracted to positive electrode, negative charge, 1000s time less massive (electrons)
