Chlorine electronic configuration

Pure anhydrous aluminium chloride is a white solid at room temperature. It is composed of double molecules in which a chlorine atom attached to one aluminium atom donates a pair of electrons to the neighbouring aluminium atom thus giving each aluminium the electronic configuration of a noble gas. By doing so each aluminium takes up an approximately tetrahedral arrangement (p. 41). It is not surprising that electron pair donors are able to split the dimer to form adducts, and ether, for example, forms the adduct. 

Elements at the right of the periodic table tend to gam electrons to reach the elec tron configuration of the next higher noble gas Adding an electron to chlorine for exam pie gives the anion Cl which has the same closed shell electron configuration as the noble gas argon... 

Transfer of an electron from a sodium atom to a chlorine atom yields a sodium cation and a chloride anion both of which have a noble gas electron configuration... 

Chlorine can exist in both positive and negative oxidation states. What is the maximum (a) positive and (b) negative oxidation number that chlorine can have (c) Write the electron configuration for each of these states, (d) Explain how you arrived at these values. 

Chlorine would have to lose seven electrons to reach an electron configuration like that of neon. But if it gained one, it would have the same stable electron configuration as argon. So that is what chlorine does. If it meets an atom with a high-energy valence electron, such as sodium, the electron migrates to the chlorine atom and forms a chloride ion ... 

On another sheet of paper, write out the electron configurations for carbon, hydrogen, nitrogen, oxygen, bromine, chlorine, and iodine. 

On the basis of the number of holes and the electron configurations, identify the different colored balls as carbon, hydrogen, nitrogen, and oxygen. Label them in Data Table 1. (The colors of bromine, chlorine, and iodine have already been recorded for you.)... 

The heat of the flame vaporises the compound, producing some sodium and chlorine atoms (electron configuration of Na 1 s2 2s2 2p6 3s1). 

Next, we need to distribute the remaining electrons to achieve a noble gas electron configuration for each atom. Since four electrons were used to form the two covalent single bonds, fourteen electrons remain to be distributed. By convention, the valence shells for the terminal atoms are filled first. If we follow this convention, we can close the valence shells for both the nitrogen and the chlorine atoms with twelve electrons. 

Chlorine as a free element is diatomic (Cl2) however, as an ion, it will gain one electron to become isoelectronic with argon. The electronic configuration of the chloride ion is s22s22p63s23p6. The compound thus formed, aluminum chloride, has the formula A1C13. 

Figure 11.1 Simple model of valency and bonding. The sodium atom (Z = 11) has electronic configuration ls22s22p63s1, drawn simply as (2, 8, 1) (i.e., showing all the n = 2 electrons as a single orbital). Chlorine (Z = 17) is s22s22p63s23p5, drawn as (2, 8, 7). In bonding to form the ionic compound NaCl, the outer (3s) electron of Na is donated to the outer orbital of Cl, giving both a full outer orbital of eight electrons, and leaving the sodium one electron short (i.e., the Na+ ion) and chlorine one extra (Cl-).

Sodium loses its valence electron and its electron configuration becomes identical to that of neon Is2 2s2 2p6. Likewise, the valence shell of chlorine becomes completely filled and its electron configuration resembles that of argon. As a result, during the reaction... 

Use the aufbau principle to write complete electron configurations and complete orbital diagrams for atoms of the following elements sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, and argon (atomic numbers 11 through 18). 

The possible states of electrons are called orbitals. These are indicated by what is known as the principal quantum number and by a letter—s, p, or d. The orbitals are filled one by one as the number of electrons increases. Each orbital can hold a maximum of two electrons, which must have oppositely directed spins. Fig. A shows the distribution of the electrons among the orbitals for each of the elements. For example, the six electrons of carbon (B1) occupy the Is orbital, the 2s orbital, and two 2p orbitals. A filled Is orbital has the same electron configuration as the noble gas helium (He). This region of the electron shell of carbon is therefore abbreviated as He in Fig. A. Below this, the numbers of electrons in each of the other filled orbitals (2s and 2p in the case of carbon) are shown on the right margin. For example, the electron shell of chlorine (B2) consists of that of neon (Ne) and seven additional electrons in 3s and 3p orbitals. In iron (B3), a transition metal of the first series, electrons occupy the 4s orbital even though the 3d orbitals are still partly empty. Many reactions of the transition metals involve empty d orbitals—e.g., redox reactions or the formation of complexes with bases. 

The charges on the chlorine, potassium, and calcium ions result from a strong tendency of valence electrons to adopt the stable configuration of the inert gases, with completely filled electronic shells. Notice that the 3 ions have electronic configurations identical to that of inert argon. 

What are the electron configurations of a chlorine anion, an argon atom, and a potassium cation ... 

Oxygen atom with p4 effective electron configuration has terms similar to those of carbon with pi effective configuration. But since the subshell is more than half-filled for oxygen, the multiplet manifold is inverted SP2, Pi, SP0. For sodium atom, 3 P1/2 level lies below 3aP3/s but for chlorine atom the order is reversed. The case for Tbs+ is already mentioned above. 

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