Sodium carbonate is used to treat cottonseed, extrude clay, and form compounds such as zinc, aluminum, and iron(II) carbonate. It has other applications as well and is used in the cotton and brick industries. Sodium carbonate, for example, is an additive that is used as a stabilizer and raising and anti-caking agent. It is also used to produce sodium vapor lamps and soaps. The element is also added to alloys and used to process molten metals and to descal metals. It is also a biocide and preservative and inhibits the growth of gram-positive and gram-negative bacteria. Azide, for example, is used for inorganic and organic synthesis and to produce airplane escape chutes and car airbags.

There are different commercial applications, but it is mostly used to produce triphenylphosphine, indigo, and sodium azide and borohydride. When reacting with ice, snow, and water, it forms hydrogen and sodium hydroxide. The element reacts with metallic halides, hydrogen, ammonia, and water. Sodium also forms organosodium compounds, solides, and electrides. There are three isotopes and different compounds such as carbonates, nitrates, sulfates, and halides. It is a good electrical conductor with a silvery color. This metal has a relatively low melting point and is reactive and soft. It occurs in sodium salts and minerals, including rock salt, sodalite, and feldspars. Purcell, Chemistry and Chemical Reactivity, 2nd ed., 1991.Sodium (atomic number 11, symbol Na) is a metal and a chemical element that was discovered in 1807 by the Cornish inventor and chemist Humphry Davy. Table 2.1.3: Properties of Selected Isotopes Element (Note: we will discuss the derivation of the atomic mass in the next section). The properties of some common isotopes are in Table 2.1.3.

Many elements other than carbon have more than one stable isotope tin, for example, has 10 isotopes. The nucleus of 14C is not stable, however, but undergoes a slow radioactive decay that is the basis of the carbon-14 dating technique used in archeology. In addition to 12C, a typical sample of carbon contains 1.11% 13C, with 7 neutrons and 6 protons, and a trace 14C, with 8 neutrons and 6 protons. Consequently, it is more often written as 12C, which is read as “carbon-12.” Nevertheless, the value of Z is commonly included in the notation for nuclear reactions because these reactions involve changes in Z.įigure 2.12: Formalism used for identifying specific nuclide (any particular kind of nucleus)Īlthough carbon-12 is the most abundant type of isotope in carbon, it is not the only isotope. The subscript indicating the atomic number is actually redundant because the atomic symbol already uniquely specifies Z. The isotope of carbon that has 6 neutrons is therefore 12 6C. An isotope of any element can be uniquely represented as A ZX, where X is the atomic symbol of the element, A is the mass number and Z is the atomic number. In a typical sample of carbon-containing material, 98.89% of the carbon atoms also contain 6 neutrons, so each has a mass number of 12. The element carbon (C) has an atomic number of 6, which means that all neutral carbon atoms contain 6 protons and 6 electrons.

Mass Number(A) = Number of Protons + Number of Neutrons Because different isotopes of the same element haves different number of neutrons, each of these isotopes will have a different mass number(A), which is the sum of the number of protons and the number of neutrons in the nucleus of an atom. All isotopes of an element have the same number of protons and electrons, which means they exhibit the same chemistry. Atoms that have the same number of protons, and hence the same atomic number, but different numbers of neutrons are called isotopes. Unlike protons, the number of neutrons is not absolutely fixed for most elements. Recall that the nuclei of most atoms contain neutrons as well as protons. Hence, the atomic number defines the element in question. If you change the atomic number to 12, you are no longer dealing with sodium atoms, but magnesium atoms. That means that all sodium atoms have 11 protons. For example, the atomic number (z) for sodium (Na) is 11. The symbol for the atomic number is designated with the letter Z. This number is known as the atomic number, which identifies the number of protons in the nucleus of ALL atoms in a given element. When you study the periodic table, the first thing that you may notice is the number that lies above the symbol.

Sodium element sybole