14 terms

Atom quiz

John Dalton
said elements were made of atoms which were immutable and that all atoms of an element are the same
J.J. Thompson
during an experiment, he learned that a gas gave off rays that were repelled by negative charges and attracted by positive charges. he called these corpuscles, but they now are called electrons
Ernest Rutherford
fired + charged particles at gold leaf, most particles went through and only a few were repelled, discovered that atoms were mostly empty space and that the nucleus was made of + charged particles and was surrounded by - charged parrticles
Neil Bohr
he determined that - charges were not just on the outside they occupied certain energy levels that were definite orbits around the nucleus
Modern atomic model
there are no REAL orbits but a large region or cloud where electrons exist. depending on how close the electron is to the nucleus, the higher the energy lavel of the atom (there are 7 known energy levels)
1 _______ takes up 1 column....... determined by outer electrons
increasing atomic number
metals, nonmetals, and metalloids are arranged by __________ __________ __________
determined by the electron levels in the electron cloud................. are rows
valence electrons
the number of outermost electrons only
an atoms volume (increases, decreases) from left to right across a row on the periodic table
an atoms volume (increases, decreases) down a column on the periodic table
on the left side of the zig-zag line
on the right side of the zig-zag line
the elements touching the either side of the zig-zag line