CEM 141 Lecture Notes - Lecture 2: Mass, Subatomic Particle, Cathode Ray Tube
Document Summary
Believed atoms(nm) are not to be cut. Believed everything came from earth, fire, air and water. Atoms were in constant motion based on watching the movement of specks of dust in sunlight. Brownian motion-( there was nothing or a void between them. ) Atoms of different elements had different shapes and sizes. Molecular properties affect how things are observed. Atoms can"t have color because they don"t reflect visible light. Questions pertaining to dalton"s atomic theory: elements are composed of small indivisible indestructible particles called atoms (no because there are protons , neutrons and electrons) All atoms of an element are identical and have the same mass and properties (no because there is the presence of isotopes) Atoms of a given element are different from atoms of other elements (yes) Compounds are formed by combinations of atoms of 2 or more elements (yes) 5. chemical reactions are due to the rearrangements of atoms; atoms(matter) are neither created nor destroyed. (yes)
