Chemistry

5. an atom that has more electrons than protons
7. scale measures how acidic or alkaline a substance is
8. n element is a pure substance that cannot be broken down into smaller parts or changed into another substance.
9. an atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons
10. particles of the chemical elements.
11. a colorless, odorless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air.
13. an ion, or charged particle, with a positive charge.

1. burner consists of a metal tube on a base with a gas inlet at the lower end of the tube, which may have an adjusting valve
2. a small localized object which can be described by several physical or chemical properties, such as volume, density, or mass.
3. rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products.
4. a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
6. reaction a process where one or more substances (reactants) are transformed into different substances (products) by rearranging their atoms to form new chemical bonds.
7. a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign.
12. an uncharged atomic particle that has a mass nearly equal to that of the proton and is present in all known atomic nuclei except the hydrogen nucleus.