Chpt 5 Flashcards
Daltons Model (disproven)
- elements made indivisible, indestructible particles called atoms
- all atoms of element are identical & have same properties
Daltons Model (true)
- atoms of different elements combine forming compounds
- compounds contain atoms in small whole number ratios
- atoms can combine in more than than one way to form different compounds
Thompsons Model
dense positive charge w/ negative charge electrons interspersed
Rutherfords Gold foil experiment
alpha particles were directed at a thin sheet. most passed few deflected -> atomic nucleus
a) if plum pudding model correct, alpha particles would pass without deflection
b) since small number deflected -> idea most of mass and all +charge of atom concentrated in space smaller than nucleus size
atomic number
(Z) number of protons (also # electrons if a neutral atom)
Mass number
(A) total # of protons & neutrons in nucleus of atom
similarities b/t protons electrons
protons and electrons same -> atom neutral
isotopes
- atoms of same element with different number of neutrons
- have same atomic number
amu
atomic mass number
electromagnetic radiation
type of energy travels thru space at 3.0 x 10^8 m/s exhibits wave and particle like behavior.
e.g. light
wavelength (lamba)
distance between adjacent wave crests
frequency (v)
of cycles or crests that pass thru stationary point in one sec.
white light
continuous spectrum
light
visible radiant energy
visible spectrum
region of light spectrum our eyes can see
radiant energy spectrum (EM spectrum)
continuous spectrum of visible and invisible light that ranges from short to long lamba.
