Phosgene, Cl,C=0, has a smaller dipole moment than formaldehyde, H2C=O, even though it contains electronegative chlorine atoms in place of hydrogen. Explain.

Consider the following chemical reaction between component A and B: A(?) + 2B(g) → C(g)+ 3D(l) …..ΔH°r = −2253.2 kJ i. State whether the reaction is exothermic or endothermic. ii. Based on the value of heat of reaction, explain the chemical reaction above in terms of the energy associated with breaking or formation of molecular bonds. iii. Consider a similar reaction of A and B as the one shown above. However, the reaction now generates D in vapor form instead of liquid. Explain how the heat of reaction value differs from the one shown above. iv. If the above reaction occurs in an isothermal system where there is no work interaction and both kinetic and potential energy changes are too small such that they are negligible, write the energy balance for the system.

5. Arrange the following compounds in the order of decreasing strength of London dispersion forces. (a) CCI4, CF4, CBr4 (b) CH4, CH3CH3, CH3CH2CH3 (c) Ar, He, Ne

Which substance in each of the following pairs would you expect to have the higher boiling point? (a) Ne or Xe, (b) CO2 or CS2, (c) CH4 or Cl2, (d) F2 or LiF, (e) NH3 or PH3 (a) Ne; (b) CS2; (c) CH4; (d) F2 ; (e) NH3 (a) Xe; (b) CS2; (c) Cl2; (d) LiF ; (e) PH3 O (a) Xe; (b) CS2; (c) Cl2; (d) LiF ; (e) NH3 (a) Xe; (b) CS2; (c) Cl2; (d) F2 ; (e) NH3 (a) Xe; (b) C02; (c) CH4 ; (d) LiF ; (e) PH3

Which member of each of the following pairs of substances would you expect to have a higher boiling point?   (a) O2 and Cl2, (b) SO2 and CO2, (c) HF and HI

2S03(g) →2SO2(g) + O2(g); AH° =

Which of the following liquids is held together by hydrogen bonding? i) methano      l ii) petrol   iii) glycerol       iv) ethanal (acetaldehyde) Using your knowledge of Lewis structures, deduce the structure of the cation PF4+.   What is its true shape and F-P-F bond angle?

Rank the elements or compounds in the table below in decreasing order of their boiling points. That is, choose 1 next to the substance with the highest boiling point, choose 2 next to the substance with the next highest boiling point, and so on. chemical symbol, substance chemical formula boiling point or Lewis structure A CO |(Choose one) O2 |(Choose one) ♥ В H H .. Н — О — C H. |(Choose one) v C - | H H Al, O, |(Choose one) ? :0 :

2(a) Provide the Lewis structures for both CH3OH and C2H3Cl. 2(b) What is the largest bond angle among all the bond angles in CH3OH and C2H3Cl? Listthe three atoms making this largest bond angle, and estimate the value of the angle.2(c) What intermolecular forces are present(i) between CH3OH molecules?(ii) between C2H3Cl molecules?