21 questions-atomic structure and periodic table Flashcards
State the masses of the sub-atomic particles.
proton-1
neutron-1
electron-almost 0
state the relative charges of the subatomic particles
proton-+1
neutron-0
electron-0
what did the gold foil expirement prove
that atoms have a small dense nucleus in the center with a positive charge
whats the atomic number of an atom
the number of protons or electrons in an atom
whats the mass number of an atom
sum of protons+neutrons in an atom
what did chadwick discover
that neutrons exist
what did bohrs expirement show
that electrons orbit in specific energy shells
whatre isotopes
atoms of the same element with different neutron numbers
what can the group number tell you about an atom of an element in that group
the number of electrons in the outermost shell of an atom
what does the period number tell you ab an atom of an element in that period
the number of electron shells in an atom
who discovered the plum pudding model
jj.thompson
why did mendeleec only put some elements into groups
they had similar properties, ex-reacted vigourously with water
who did the alpha particle scattering expirement
ernest rutherford
whats the elctronic structure of an element in group 4 period 3
2,8,4
why did mendeleev leave gaps in the periodic table
for elements that havent yet been discovered