The measured strength of ionic bonding is called the lattice energy. SURVEY . What is the relationship between atomic mass and formula mass? The attractive forces between ions are isotropic—the same in all directions—meaning that any particular ion is equally attracted to all of the nearby ions of opposite charge. Use the periodic table to explain why this should not surprise you. Write the electron configuration for the monatomic ions formed from the following elements (which form the greatest concentration of monatomic ions in seawater): Write out the full electron configuration for each of the following atoms and for the monatomic ion found in binary ionic compounds containing the element: (a) 1s22s22p63s23p1; Al3+: 1s22s22p6; (b) 1s22s22p63s23p63d104s24p5; 1s22s22p63s23p63d104s24p6; (c) 1s22s22p63s23p63d104s24p65s2; Sr2+: 1s22s22p63s23p63d104s24p6; (d) 1s22s1; Li+: 1s2; (e) 1s22s22p63s23p63d104s24p3; 1s22s22p63s23p63d104s24p6; (f) 1s22s22p63s23p4; 1s22s22p63s23p6, From the labels of several commercial products, prepare a list of six ionic compounds in the products. (b) Chlorine is a pale yellow-green gas. Thus, the formula for this ionic compound is Fe, Potassium ions have a charge of 1+, while sulfate ions have a charge of 2−. Solution Br, N, F, and S would form anions. Ionic bonding results into one type of structure, the giant ionic structure. The charges of anions formed by the nonmetals may also be readily determined because these ions form when nonmetal atoms gain enough electrons to fill their valence shells. A set of oppositely charged ions that compose an ionic compound. Transition and inner transition metal elements behave differently than main group elements. 4. The properties of ionic compounds shed some light on the nature of ionic bonds. Care must be taken when calculating formula masses for formulas containing multiple polyatomic ions because the subscript outside the parentheses refers to all the atoms in the polyatomic ion. One way atoms obtain eight electrons in the valence shell is for some atoms to lose electrons while other atoms gain them. An attraction between oppositely charged ions. The formula mass is the sum of the atomic masses of the atoms in the formula. The two additional electrons required to fill the valence orbitals give the oxide ion the charge of 2– (O2–). Chemical formulas for ionic compounds are determined by balancing the positive charge from the cation(s) with the negative charge from the anion(s). What are the chemical formulas of the ionic compounds these ions make with the oxide ion, O. S3.1.1. Thus, it is simple to determine the charge on such a negative ion: The charge is equal to the number of electrons that must be gained to fill the s and p orbitals of the parent atom. We can think about the formation of such compounds in terms of the periodic properties of the elements. Ions can be positively charged or negatively charged. Some lattice energies are given in Table 9.1 “Lattice Energies of Some Ionic Compounds.” For example, calcium is a group 2 element whose neutral atoms have 20 electrons and a ground state electron configuration of 1s22s22p63s23p64s2. When the inner transition metals form ions, they usually have a 3+ charge, resulting from the loss of their outermost s electrons and a d or f electron. AlO. Which of the following atoms would be expected to form negative ions in binary ionic compounds and which would be expected to form positive ions: P, I, Mg, Cl, In, Cs, O, Pb, Co? The protons in the nucleus do not change during normal chemical reactions. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Ionic solids are also poor conductors of electricity for the same reason—the strength of ionic bonds prevents ions from moving freely in the solid state. The protons in the nucleus do not change during normal chemical reactions. Mercury (group 12) also exhibits an unexpected behavior: it forms a diatomic ion, [latex]{\text{Hg}}_{2}{}^{\text{2+}}[/latex] (an ion formed from two mercury atoms, with an Hg-Hg bond), in addition to the expected monatomic ion Hg2+ (formed from only one mercury atom).