Chapter 3

a. Determine whether each of the following compounds is likely to exist as a molecule, or as an ionic compound: i. Hydrogen fluoride; HF ii. Silicon tetrachloride; \(\mathrm{SiCl}_{4}\) iii. Elemental sulfur as \(\mathrm{S} 8\) iv. Disodium dioxide; \(\mathrm{Na}_{2} \mathrm{O}\) v. \(\mathrm{PF}_{3}\) vi. \(\mathrm{Be}_{3} \mathrm{~N}_{2}\) vii. AlP viii. CBr4

a. Sodium and chlorine are both third-period elements. Draw Lewis diagrams for each of these elements. b. What number of electrons would chlorine have to gain in order to achieve a "noble gas configuration"? What would be the charge on chlorine? c. What number of electrons would Na have to lose to obtain the noble gas configuration of Ne with eight valence electrons? What charge would Na have?

a. Hydrogen and oxygen react to form water, \(\mathrm{H}_{2} \mathrm{O}\). Draw a Lewis diagram for water using the line-bond shorthand. b. Draw the Lewis diagram for the molecules, hydrogen chloride, \(\mathrm{BrCl}\), and hydrogen cyanide (HCN).

Write a correct chemical formula for each of the following ionic compounds: a. Sodium phosphide b. Iron (II) nitrite c. Calcium hydrogen phosphate d. Chromium (III) oxide

Write a proper chemical name for each of the following ionic compounds: a. \(\mathrm{NaBr}\) b. \(\mathrm{CuCl}_{2}\) c. \(\mathrm{Fe}\left(\mathrm{NO}_{3}\right)_{3}\) d. \(\left(\mathrm{NH}_{4}\right) 3 \mathrm{PO}_{4}\)