Atoms,Elements, Molecules, and Compounds Flashcards
Atom
The smallest particle of an element that can exist.
Element
A pure chemical substance that cannot be physically split into a more simple substance. Each is made of one type of atom. Carbon,mercury and hydrogen are examples.
Molecule
The smallest particle of a substance that can exist.It is composed of two or more atoms.
Compound
A substance made of atoms from two or more different elements.
Proton
A particle of matter that has a positive electrical charge and found in the nucleus of an atom. (proton–>Positive)
Neutron
A particle of matter that has no electrical charge and found in the nucleus of an atom. (Neutron–>No charge)
Electron
A Particle of matter that has a negative electrical charge and travels around the nucleus of an atom.
Atomic Number
= the number of protons in an element’s atoms. Top number in the element box.
Mass Number
Number of protons plus neutrons. Bottom number in the element box.
Chemical symbol
A one or two letter representation of an element.
Subscript
A tiny number to the right of the element symbol. Tells you how many atoms of that element.