9.26 Calculate the lattice energy of calcium chloride given that the heat of sublimation of Ca is 121 kJ/mol and DH°f (CaCl2) 5 2795 kJ/mol. (See Tables 8.2 and 8.3 for other data.)h e Covalent BondReview Questions9.27 What is Lewis’s contribution to our understanding of the covalent bond?9.28 What is the difference between a Lewis dot symbol and a Lewis structure?9.29 How many lone pairs are on the underlined atoms in these compounds? HBr, H2S, CH4.9.30 Distinguish among single, double, and triple bonds in a molecule, and give an example of each.Electronegativity and Bond TypeReview Questions9.31 Define electronegativity, and explain the difference between electronegativity and electron afi nity. De-scribe in general how the electronegativities of the elements change according to position in the periodic table.9.32 What is a polar covalent bond? Name two compounds that contain one or more polar covalent bonds.Problems9.33 List these bonds in order of increasing ionic character: the lithium-to-l uorine bond in LiF, the potassium-to-oxygen bond in K2O, the nitrogen-to-nitrogen bond in N2, the sulfur-to-oxygen bond in SO2, the chlorine-to-l uorine bond in ClF3.9.34 Arrange these bonds in order of increasing ionic character: carbon to hydrogen, l uorine to hydrogen, bromine to hydrogen, sodium to chlorine, potassium to l uorine, lithium to chlorine.9.35 Four atoms are arbitrarily labeled D, E, F, and G. Their electronegativities are: D 5 3.8, E 5 3.3, F 5
2.8, and G 5 1.3. If the atoms of these elements form
the molecules DE, DG, EG, and DF, how would you
arrange these molecules in order of increasing cova-lent bond character?
9.36 List these bonds in order of increasing ionic charac-ter: cesium to l uorine, chlorine to chlorine, bromine
to chlorine, silicon to carbon.
đang được dịch, vui lòng đợi..