Phosphorus—hydrogen bonds elemental halogens

Carbon atoms readily form covalent bonds with other carbon atoms and with atoms of other nonmetals, especially hydrogen, nitrogen, oxygen, phosphorus, sulfur, and the halogens. Carbon atoms form these bonds by sharing pairs of electrons with atoms of other elements. When two atoms share two electrons, the bond is called a single bond (symbolized in a structural formula by a single dash - ). When four electrons are shared, the bond is called a double bond (symbolized by a double dash = ). When six electrons are shared, the bond is called a triple bond (symbolized by a triple dash <=> ). A carbon atom will... 

Under terrestrial conditions most elements rarely exist as isolated atoms. The atoms of most known elements are chemically bonded to other atoms. For example, oxygen, nitrogen, hydrogen, and the halogens are diatomic molecules. Yellow sulfur and white phosphorus exist as molecules whose formulas are S, and P4, respectively. The molecules of diamond or graphite (both forms of carbon) and of red phosphorus consist of many millions of atoms. Metallic elements, too, such as copper and potassium, are composed of bonded atoms, generally in a crystalline form. 

The number of covalent bonds formed by an atom is termed its COVALENCY. The covalency of an atom is equal to the number of electrons the atom needs to become isoelectronic with a noble gas. Some of the more common elements have the following covalencies when they follow the octet rule and also have no charge hydrogen and the halogens, 1 oxygen and sulfur, 2 nitrogen and phosphorus, 3 carbon and silicon, 4. LEWIS ELECTRONIC FORMULAS, in which bonds and unshared electrons are shown, are given for a few typical compounds of these elements ... 

Organic compounds Substances whose molecules contain one or more carbon atoms covalently bonded with another element (including hydrogen, nitrogen, oxygen, the halogens as well as phosphorus, silicon and sulfur). 

Carbon atoms form bonds readily with hydrogen, oxygen, and nitrogen. Carbon also may combine with halogen elements (fluorine, chlorine, bromine, iodine), with phosphorus and sulfur, and, less often, with other elements. 

Most of the common elements in organic compounds—C, N, O, and the halogens— follow the octet rule. Hydrogen is a notable exception, because it accommodates only two electrons in bonding. Additional exceptions include boron and beryllium (second-row elements in groups 3A and 2A, respectively), and elements in the third row (particularly phosphorus and sulfur). 

Identify the most common number of covalent bonds and lone pairs for the atoms of each of the following elements hydrogen, the halogens (group 17), oxygen, sulfur, selenium, nitrogen, phosphorus, and carbon. 

Carbon atoms form strong bonds not only with other carbon atoms but also with atoms of other elements. In addition to hydrogen, many carbon compounds also contain oxygen. Nitrogen, sulfur, phosphorus, and the halogens also frequently occur in carbon compounds. 

Organic chemistry is the chemistry of compounds of carbon. There are several million organic compounds, 10-fold more than inorganic compounds. This occurs because carbon atoms easily bond to each other as well as to other elements, principally hydrogen, oxygen, halogen (fluorine, chlorine, bromine, iodine), nitrogen, sulfur, and phosphorus, in a variety of structural patterns. 

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