the number two; 2

(bound form) sulfur; a nonmetallic chemical element with the symbol S

(bound form) a group of atoms that behave as a single unit in a chemical reaction; a radical

Fossilized resin of ancient pine and cypress trees, appearing as a translucent yellow, brown, or reddish-brown solid; used for making lacquer, ornaments, and in traditional medicine.

acid, a chemical compound that releases hydrogen ions in water

sodium; natrium (chemical element Na)