physics 1

compound

homogenous combination

molecules

smallest component of a compound that retains its characteristics

atoms

smallest component of an element

elements

all matter is composed of a limited number of elements (105)

electron charge and mass

-1; 0.9108×10^-27

proton charge and mass

+1; 1.6724×10^-24

proton relative mass

1836

neutron charge and mass

0; 1.6747×10^-24

neutron relative mass

1840

ernest rutherford gold foil explained

learned that atoms have small, compact nucleus; atoms are primarily empty space; therefore, the radiation was able to travel mostly through the gold foil.

nuclear density is

10^12 gm/cm³

what did bohr discover about electrons

they exist in closed orbits- “shells”. energy only changes when electrons change orbits

bohr: quantum numbers define…

shell/subshell structure

which shell has the highest binding energy

k shell

which shell has the lowest binding energy

m shell

electrons with lowest energy are located

closest to the nucleus (in the k shell, where binding energy is high)