quiz #1 Flashcards
review for lectures 1&2
postulates of Dalton’s atomic theory (1)
matter is composed of small particles called atoms; atoms are the smallest unit of an element that can participate in chemical change; atoms are indivisible
postulates of Dalton’s atomic theory (2)
element consists of one type of atom which has a characteristic mass and is the same for all atoms of that element; atoms of one element cannot be converted into atoms of another element
postulates of Dalton’s atomic theory (3)
atoms in one element differ in properties from atoms in all other elements; atoms of the same element are identical in mass and properties
postulates of Dalton’s theory (4)
a compound consists of atoms of two or more elements combined chemically in a specific small whole number ratio.
postulates of Dalton’s theory (5)
atoms are neither created nor destroyed during a chemical change, simply rearranged to yield different substances.
element
simplest type of matter with unique physical/chemical properties
compound
matter composed of two or more elements that are chemically bound together
atom
smallest particles of matter; cannot be destroyed or created
isotope
atoms of an element with a different number of neutrons
law of conservation of mass
in a chemical reaction mass is neither created nor destroyed
law of definite proportions
compounds will always have the same proportions (ratios) of their constituent elements (ex: H2O)
law of multiple proportions
when two elements form two different compounds, a fixed mass of one element reacts with masses of the other element in a ratio of small, whole numbers
J.J. Thomson
find out electrons are lighter than atoms, he had the cathode ray tube experiment
Miliken
determined the charge and mass of the electron, oil drop experiment
Rutherford
came up with the idea that atoms consist of tiny massive positive nucleus surrounded by electrons
