chemical reaction

a quantitative statement describing the interaction between two materials (or compounds or species), the reactants, that leads to the generation of different materials, the products.

    example: 2NO + 3O₃ -> N₂O₅+3O₂

_{in a neutrally charged atom or molecule, the number of protons equals the number of electrons.}

_{electrons are held in orbitals that can hold either 2 or 8 electrons and are paired with electrons of opposite spin (+ or -)}

compounds often form in order to fill their orbitals by sharing electrons

compounds in which the orbitals are filled tend to be very stable and unreactive (noble gasses such as helium, neon, and argon or molecules like H₂0)