There are five general aspects of the oxidation-reduction chemistry:. With the exception of most of the noble gases, all nonmetals form compounds with oxygen, yielding covalent oxides. Most of these oxides are acidic, that is, they react with water to form oxyacids. Recall from the acid-base chapter that an oxyacid is an acid consisting of hydrogen, oxygen, and some other element.
There are three characteristics of these acidic oxides:. The binary hydrogen compounds of the nonmetals also exhibit an acidic behavior in water, although only HCl, HBr, and HI are strong acids. The acid strength of the nonmetal hydrogen compounds increases from left to right across a period and down a group. Water, H 2 O, is also a weaker acid than is hydrogen sulfide, H 2 S , which is weaker than is hydrogen selenide, H 2 Se.
Weaker acidic character implies greater basic character. The structures of the nonmetals differ dramatically from those of metals. Metals crystallize in closely packed arrays that do not contain molecules or covalent bonds. Nonmetal structures contain covalent bonds, and many nonmetals consist of individual molecules. The electrons in nonmetals are localized in covalent bonds, whereas in a metal, there is delocalization of the electrons throughout the solid.
The noble gases are all monatomic, whereas the other nonmetal gases—hydrogen, nitrogen, oxygen, fluorine, and chlorine—normally exist as the diatomic molecules H 2, N 2 , O 2 , F 2 , and Cl 2. The other halogens are also diatomic; Br 2 is a liquid and I 2 exists as a solid under normal conditions. The changes in state as one moves down the halogen family offer excellent examples of the increasing strength of intermolecular London forces with increasing molecular mass and increasing polarizability.
Oxygen has two allotropes: O 2 , dioxygen, and O 3 , ozone. Phosphorus has three common allotropes, commonly referred to by their colors: white, red, and black. Sulfur has several allotropes. There are also many carbon allotropes.
Most people know of diamond, graphite, and charcoal, but fewer people know of the recent discovery of fullerenes, carbon nanotubes, and graphene. Descriptions of the physical properties of three nonmetals that are characteristic of molecular solids follow. Carbon occurs in the uncombined elemental state in many forms, such as diamond, graphite, charcoal, coke, carbon black, graphene, and fullerene.
Each atom forms four single bonds to four other atoms at the corners of a tetrahedron sp 3 hybridization ; this makes the diamond a giant molecule. These properties relate to its structure, which consists of layers of carbon atoms, with each atom surrounded by three other carbon atoms in a trigonal planar arrangement.
Each p orbital is perpendicular to the plane of carbon atoms. London dispersion forces hold the layers together. To learn more, see the discussion of these weak forces in the chapter on liquids and solids.
Other forms of elemental carbon include carbon black, charcoal, and coke. Carbon black is an amorphous form of carbon prepared by the incomplete combustion of natural gas, CH 4. It is possible to produce charcoal and coke by heating wood and coal, respectively, at high temperatures in the absence of air. Recently, new forms of elemental carbon molecules have been identified in the soot generated by a smoky flame and in the vapor produced when graphite is heated to very high temperatures in a vacuum or in helium.
One of these new forms, first isolated by Professor Richard Smalley and coworkers at Rice University, consists of icosahedral soccer-ball-shaped molecules that contain 60 carbon atoms, C Graphene and carbon nanotubes are two recently discovered allotropes of carbon.
Both of the forms bear some relationship to graphite. Graphene is a very strong, lightweight, and efficient conductor of heat and electricity discovered in As in graphite, the carbon atoms form a layer of six-membered rings with sp 2 -hybridized carbon atoms at the corners. Resonance stabilizes the system and leads to its conductivity. Unlike graphite, there is no stacking of the layers to give a three-dimensional structure.
The simplest procedure for preparing graphene is to use a piece of adhesive tape to remove a single layer of graphene from the surface of a piece of graphite. This method works because there are only weak London dispersion forces between the layers in graphite. Physics 20 cards. Which term explains whether an object's velocity has increased or decreased over time.
Which of these is a characteristic of nonmetals. What is the only factor needed to calculate change in velocity due to acceleration of gravity 9.
What term is used to describe splitting a large atomic nucleus into two smaller ones. Vaping Study Guide 3 cards. Propylene Glycol. Q: Which nonmetals exist as a diatomic solid? Write your answer Related questions. What are some similarities that exist among the elements in Group 7? What element does not exist as a diatomic molecule?
What element is solid diatomic? What is a diatomic solid? Which atoms do not exist as a diatomic molecules?
Is silicon a Diatomic Molecule? How do halogen molecules exist? Does sodium exists as a diatomic molecule? When two identical nonmetals are bonded together the result is? Is nickel a diatomic molecule? Readily forming diatomic molecules is a property of?
Which elements exist as diatomic molecules? What Types of elements to covalent bonds join together? What element occurs naturally as a diatomic solid? What elements do not exist as a diatomic molecule? Is nitrogen always exist in diatomic form? What family of elements most often exist as diatomic molecules? Can hydrogen with one electron exist as a solid? Which nonmetals are solid? Would hydrogen exist as a molecule?
Does hydrogen exist as a diatomic molecule? Why can't diatomic elements exist on their own? Which elements exist naturally as diatomic molecules? She has taught science courses at the high school, college, and graduate levels.
Facebook Facebook Twitter Twitter. Updated October 04, Key Takeaways: Diatomic Elements Diatomic elements are pure elements that form molecules consisting of two atoms bonded together.
There are seven diatomic elements: hydrogen, nitrogen, oxygen, fluorine, chlorine, iodine, bromine. These elements can exist in pure form in other arrangements. For example, oxygen can exist as the triatomic molecule, ozone. Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. What Are the 7 Diatomic Elements? Liquid Elements on the Periodic Table. What Element in the Halide Family is a Liquid? Bromine Facts Atomic Number 35 or Br. Chemical Element Pictures - Photo Gallery.
Element Families of the Periodic Table. Hydrogen Facts - H or Atomic Number 1.
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