The smallest particle of an element that retains its identity in a chemical reaction
scanning tunneling microscope
an instrument used to generate images of individual atoms
english chemist and schoolteacher who formulated a theory to describe the structure and chemical reactivity of matter in terms of atoms
Greek philosopher who was among the first to suggest the existence of atoms
negatively charged particles found outside the nucleus
a stream of electrons produced at the negative electrode (cathode) of a tube containing a gas at low pressure
positively charged particles located in the nucleus
subatomic particles with no charge
the center of the atom which contains the protons and neutrons
the number of protons in the nucleus of an atom
an arrangement of elements according to similarities in their properties
the sum of the numbers of protons and neutrons in the nucleus of an atom
a vertical column of elements in the periodic table
atoms with the same number of protons but different numbers of neutrons
atomic mass unit (amu)
1/12th of the mass of a carbon 12 atom
weighted average mass of the atoms in a naturally occurring sample of an element
a horizontal row of the periodic table
the amount of energy needed to move an electron from one energy level to another
a region in space around the nucleus of an atoms where an electron is likely to be moving
the regions around the nucleus within which the electrons have the highest probability of being found
quantum mechanical model
the modern description of the behavior of electrons in atoms
Please allow access to your computer’s microphone to use Voice Recording.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Your microphone is muted
For help fixing this issue, see this FAQ.