Which of the following statements concerning the structures below is/are true? Formal charges are not shown. You can select more than one, or none, of these statements. H A H H-CN Cy ―N=Cy―0 H-Cx-NC,=0: H H B In structure B, the formal charge of N is +1. The oxidation state of N is different for each structure. Structures B and C are nonequivalent resonance structures. In structure C, the formal charge of O is -1. On the basis of formal charges, structure B is more important than structure A. The total charge on this species is -1. 00000C C

Rank the following ionic compounds in order of lattice energy, from the least exothermic (least negative lattice enthalpy) to the most exothermic (most negative lattice enthalpy): BaO, NaF, MgO, CsBr Least exothermic ◆ ◆ 4 ◆ Most exothermic

Testosterone is an anabolic steroid. The structure of testosterone is shown below. What is the idealised bond angle at the indicated atom (ii) ? Hint: atom (iv) has been completed for you as an example. (iv) bond angle: 109.5°, geometry of the electron pairs: tetrahedral, shape of the bonds: tetrahedral ·····|||I H ····||||I ii iv

Given the bond enthalpy information below, calculate the Δ H of the following hypothetical reaction:                      A2 + 2BC  --->   A-B-A + C-A-C A-A  203.5 B-B  282.1 B-C  155.6 C-A  187 B-A  208.8 All of the above bond enthalpy values are in kJ/mole.  Report your answer in kJ/mole units.

Draw the lewis structure of the structure below

Chapters 7&8 Review What is the formal charge of nitrogen in HCN? O-1 O+1 00 O+2

Consider the incomplete structure shown. Draw an alternative Lewis (resonance) structure for the incomplete structure. Show the unshared electron pairs and nonzero formal charges in your structure. Don't use radicals.     Determine the formal charge on the nitrogen atom in the structure. If the atom is formally neutral, indicate a charge of zero.

Draw the Lewis dot structure for H₂O. What is the formal charge of the oxygen in the molecule? +1 +2 Ń

Compound Formula Name of Compound Ionic or Covalent AgBr     N2S5     Si4H10     CuSO4     Hg2I2

CO3²- Draw the molecule by placing atoms on the grid and connecting them with bonds. Include all lone pairs of electrons. Show the formal charges of all atoms in the correct structure. To change the symbol of an atom, double-click on the atom, and enter the letter of the new atom.