A mole is a SI base unit of measurement. This is a definition of unit, its value, and example problems using the mole in chemistry.| Science Notes and Projects
Learn about the main types of chemical reactions and their names. See examples and chemical equations for each type of reaction.| Science Notes and Projects
Understand the meaning of a product in chemistry. See how to recognize products and get examples in chemical reactions.| Science Notes and Projects
Learn about the Pauli exclusion principle in chemistry and physics and how it applies to the electron configuration of atoms.| Science Notes and Projects
Learn where the electrons are located in an atom and on the periodic table. Also discover the location of valence electrons.| Science Notes and Projects
December 18 is J. J. Thomson's birthday. Thomson was a British physicist who is best known for the discovery of the electron.| Science Notes and Projects
Learn what nucleons are in chemistry and physics. See how nucleons relate to the mass number and atomic mass of atoms.| Science Notes and Projects
Get the definition of a molecule. See examples of molecules and learn the different between a molecule and a compound.| Science Notes and Projects
Learn about single, double, and triple bonds. Get examples of compounds and learn the properties of these types of covalent bonds.| Science Notes and Projects
Get the coordinate covalent bond definition and examples. Another name for this bond is a dative bond or dipolar bond.| Science Notes and Projects
Learn about intramolecular forces. See the types of intramolecular forces and learn whether they are stronger than intermolecular forces.| Science Notes and Projects
Learn about valence electrons. Get the definition and a periodic table showing the number of valence electrons for each element.| Science Notes and Projects
Learn about the octet rule in chemistry. Get the definition, see examples, and learn about exceptions to the rule.| Science Notes and Projects
Learn about the noble gas configuration of atoms. Get a list of electron configurations for all 118 elements.| Science Notes and Projects
Learn about metallic bonding and see how it differs from ionic and covalent bonds. Get examples of metallic bonds.| Science Notes and Projects
Get the ionic bond definition and examples in chemistry. Learn which types of atoms participate in ionic bonding.| Science Notes and Projects
Learn what noble gases are, which elements are included in the group, and what properties distinguish a noble gas from other element of the periodic table.| Science Notes and Projects
Get the liquid definition in chemistry and other sciences. See examples of liquids in everyday life. See what is not a liquid.| Science Notes and Projects
Get the atomic nucleus definition and facts, including a look at what is inside the nucleus of an atom and how big it is.| Science Notes and Projects
Learn what a proton is, where it's found in the atom, and get interesting facts about protons.| Science Notes and Projects
Learn why protons and neutrons stick together, how close they have to be in the atomic nucleus, and how the strong force accounts for mass.| Science Notes and Projects
Learn the difference between and atom and an ion. Get definitions and examples of atoms and ions in chemistry.| Science Notes and Projects
Get the scientific definition of a crystal. Learn how crystals are classified, what their properties are, and see examples.| Science Notes and Projects