unit 7 Flashcards
electromagnetic radiation
light
Planck’s constant
allows us to relate energy and frequency; represented by “h”
rods & cones
colles in the eye which detect light
spectrometer
scientific instrument that can analyze the light in a star and determine all of the individual wavelengths that make it up-determining its elemental composition. Method known as spectroscopy. Can also be applied to chemicals
quantum assumption
electrons can jump orbit but can not be anywhere in between
excited
when an electron moves from an orbit close to the nucleus to an orbit far away from the nucleus – opposite “de-excited”
wavelength
the distance between the crests or troughs of a wave
amplitude
a measure of the height of the crests or the depths of the troughs of a wave
physical constant
a measurable quantity in nature that does not change
frequency
the number of wave crests or troughs that pass a given point each second
When wavelength is — frequency is small
large
When wavelength is small frequency is
large
as a light waves frequency increases, its energy
increases
As a light waves wavelength increases its energy
decreases
crookes tube
glass tube with a tiny amount of gas, hooked up to a battery, resulting in a faint yellow-grebe glow on the end of the tube. sometimes referred to as a cathode ray tube
Every substance on earth has
electrical charges
electron
negative element of atom that has common ration of charge to mass
proton
positively charged
nutron
neutral
Atomic number
to number on each box in the periodic table; tells how many protons
all atoms have equal numbers of
electrons and protons
isotopes
Atoms with the same number of protons but different numbers of neutrons
isotopes behave identically in their chemistry; the main difference between them is
their mass
Mass number
the total number of neutrons and protons in an atom