Block 3 training exercises.

  Draw the Lewis structures for each of the following molecules and determine the electron pair geometry and the molecular geometry as predicted by the VSEPR. 1) F2 2) N2 3) ICL 4) CO2 5) NH3 6) CF4 7) C2H6 8) C2H4 9) C2H2 10) HCN 11) SO2 12) HNO3 (the hydrogen is bonded to one of the oxygens). 13) CH4O For each of the following polyatomic ions, draw all resonance structures. Based on the formal charges identify which is the best resonance structure. (if all resonance structures are equivalent indicate so next to the structure). Indicate the bond angles as predicted by VSEPR for the best structure . 14) OH15) CN16) ClO2 – 17) ClO3 – 18) CO3 2- 19) SO3 2- 20) SCN- 21) HCO2 - 22) NO2 + State the hybridization of each of the central atom in each of the following. 23) ClO2 – 24) ClO3 – 25) CO3 2- 26) SO3 2- 27) SCN28) HCO2 - 29) NO2 - 30) Hydrogen Peroxide (H2O2) is a reactive molecule, often used an antiseptic and sometimes used for bleaching. Draw a Lewis structure for hydrogen peroxide (peroxide is a polyatomic ion). What is the oxidation state of the oxygen in hydrogen peroxide? Suggest a reason for its reactivity. 31) What is the hybridization of the central atom in Acetone CH3COCH3? 32) How many sigma bonds and how many pi bonds are in Acetone? 33) Ozone (O3) is needed in the stratosphere to absorb (and filter out) potentially damaging ultraviolet light. However, in the lower atmosphere is a dangerous pollutant as it is a very reactive form of oxygen and as a result, very toxic and destructive. Draw the two reasonable structures, include formal charges. (Hint: it is not a ring) Suggest a reason for its high reactivity 34) Which of the following reactions is associated with the lattice energy of Li2O (ΔH°latt)? A) Li2O(s) → 2 Li⁺(g) + O2⁻(g) B) 2 Li⁺(aq) + O2⁻(aq) → Li2O(s) C) 2 Li⁺(g) + O2⁻(g) → Li2O(s) D) Li2O(s) → 2 Li⁺(aq) + O2⁻(aq