What is the molecular geometry of ClF3? Label all bond angles in the structure.

Best Lewis Formula and Molecular Geometry A student writes the Lewis electron-dot formula for the carbonate anion, CO32, as a Does this Lewis formula obey the octet rule? Explain. What are the formal charges on the atoms? Try describing the bonding for this formula in valence bond terms. Do you have any difficulty doing this? b Does this Lewis formula give a reasonable description of the electron structure, or is there a better one? If there is a better Lewis formula, write it down and explain why it is better. c The same student writes the following resonance description for CO2: Is there something wrong with this description? (What would you predict as the geometries of these formulas?) d Is one or the other formula a better description? Could a value for the dipole moment help you decide? e Can you write a Lewis formula that gives an even better description of CO2? Explain your answer.

Consider the following compounds: CO2, SO2, KrF2, SO3, NF3, IF3, CF4, SF4, XeF4, PF5, TF5, and SCl6. These 12 compounds are all examples of different molecular structures. Draw the Lewis structures for each and predict the molecular structures. Predict the bond angles and the polarity of each. (A polar molecule has a net dipole moment, while a nonpolar molecule does not.) See Exercises 25 and 26 for the molecular structures based on the trigonal bipyramid and the octahedral geometries.

Bond Enthalpy When atoms of the hypothetical element X are placed together, they rapidly undergo reaction to form the X2 molecule: X(g)+X(g)X2(g) a Would you predict that this reaction is exothermic or endothermic? Explain. b Is the bond enthalpy of X2 a positive or a negative quantity? Why? c Suppose H for the reaction is 500 kJ/mol. Estimate the bond enthalpy of the X2 molecule. d Another hypothetical molecular compound, Y2(g), has a bond enthalpy of 750 kJ/mol, and the molecular compound XY(g) has a bond enthalpy of 1500 kJ/mol. Using bond enthalpy information, calculate H for the following reaction. X2(g)+Y2(g)2XY(g) e Given the following information, as well as the information previously presented, predict whether or not the hypothetical ionic compound AX is likely to form. In this compound, A forms the A+ cation, and X forms the X anion. Be sure to justify your answer. Reaction: A(g)+12X2(g)AX(s)The first ionization energy of A(g) is 400 kJ/mol. The electron affinity of X(g) is 525 kJ/mol. The lattice energy of AX(s) is 100 kJ/mol. f If you predicted that no ionic compound would form from the reaction in Part e, what minimum amount of AX(s) lattice energy might lead to compound formation?

Indicate which of the following molecules are polar. Draw the molecular structure of each polar molecule, including the arrows that indicate the bond dipoles and the molecular dipole moment. (a) HCN (b) I2 (c) NO

It is possible to write a simple Lewis structure for the SO42- ion, involving only single bonds, which follows the octet rule. However, Linus Pauling and others have suggested an alternative structure, involving double bonds, in which the sulfur atom is surrounded by six electron pairs. (a) Draw the two Lewis structures. (b) What geometries are predicted for the two structures? (c) What is the hybridization of sulfur in each case? (d) What are the formal charges of the atoms in the two structures?

Successive substitution of F atoms for H atoms in the molecule NH3 produces the molecules NH2F, NHF2, and NF3. a. Draw Lewis structures for each of the four molecules. b. Using VSEPR theory, predict the geometry of each of the four molecules. c. Specify the polarity (polar or nonpolar) for each of the four molecules.

Experimental evidence indicates the existence of HC3N molecules in interstellar clouds. Write a plausible Lewis structure for this molecule.

Two different molecules have the formula C2H6O. One of the molecules has the oxygen atom bonded to both carbon atoms. The other molecule has the oxygen atom bonded to only one carbon atom while both carbon atoms are bonded to each other. Write Lewis structures for both of these compounds.

Add lone pairs to these Lewis structures of interhalogen compounds. BrF3 BrF5