Atoms are the smallest form of the substance. examples of atoms are in elemental forms such as copper, helium, silver. Diatomic molecules are made up of identical atoms. Examples are I2.. F2 and Br2. Formula units are those compounds that are made up of two or more elements such as -No2, KMnO4,<span>C3H8, MgCl2, HgBr2, Ba(OH)2</span>
You can automatically rule out CH₄ since it has no lone pairs at all around the central atom. Water has 2. Ammonia is the only Lewis structure that contains one lone pair.
Decomposed organic matter ,mud,silt ,and sand
Alchemists advanced the tools and procedures for working with chemicals. Alchemists also developed methods for sorting out mixtures and cleansing chemicals. They designed equipment that is still in use today including beakers, flasks, tongs, funnels, and the mortar and pestle. Also, Alchemists backed to an unbelievable variety of what would later be acquainted as chemical industries: basic metallurgy, metalworking, the invention of inks, dyes, paints, and cosmetics, leather-tanning, and the preparation of extracts and liquors.