How can we help?
You can also find more resources in our
Select a category
Something is confusing
Something is broken
I have a suggestion
What is your email?
What is 1 + 3?
Prentice Hall Chemistry Chapter 4
the smallest particle of an element that retains its identity in a chemical formula
believed that atoms were indivisible and and indestructible
Atomic Theory - Atoms of the same element are identical. atoms can be combined into whole number ratios
negatively charged, floating around nucleus. number is the same as protons
positively charged. inside the nucleus, same number as atomic number
no charge, inside nucleus. atomic mass - proton = # of neutrons
tiny central core of an atom composed of protons and neutrons. positively charged
gold foil experiment - atoms are made up if mostly empty space with a small dense nucleus in the center
cathode ray, discovered that electrons have a negative charge.
proposed that an electron is found only in orbits, around nucleus
the horizontal rows on a periodic table
each vertical column of the periodic table
atomic mass unit
(AMU) unit used when finding relative abundance
atoms that have the same number of protons but different number of neutrons