A basic unit of matter consisting of a dense central nucleus surrounded by a cloud of negatively charged electrons.
The total number of protons and neutrons in the nucleus of a single atom.
The number of protons in the nucleus of an atom.
An elementary subatomic particle that carries a negative electrical charge
A pure chemical substance composed of all atoms that have the same number of protons.
Different forms of the same element that has nuclei with the same number of protons but different numbers of neutrons.
A subatomic particle with no net electric charge and a mass slightly larger than that of a proton.
The central structure in an atom that contains neutrons and protons.
A subatomic particle found in the nucleus of an atom that contains a positive charge.
A stable unit of two or more atoms held together by chemical bonds.
A formation of atoms held together by ionic bonds
A type of chemical bond that often forms between metal and nonmetal ions through electrostatic attraction.
An atom or molecule that has lost or gained one or more electrons, giving it a positive or negative electrical charge.
A form of chemical bond characterized by sharing of pairs of electrons between atoms, or between atoms and other covalent bonds.
law of conservation of mass
A physical law stating that the total amount of mass in a closed system remains constant. Also stated as: mass can be neither created nor destroyed during a chemical reaction—only rearranged.
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.