Organic chemistry homework help

Organic chemistry homework help.

1. The modern definition of organic chemistry is ___.

 
 
 
 

2. Organic compounds were originally defined as compounds obtained from ___.

 
 
 
 
 

3. The bond that results when two atoms share a pair of electrons is called a ___.

 
 
 
 
 

4. Draw the Lewis structure of acetic acid, CH₃CO₂H, clearly indicating all non-bonding pairs of electrons.

 
 
 
 
 
 
 
 
 
 
 
 
 

5. 148) Even though nitrogen and phosphorus have the same number of valence electrons, nitrogen can only bond to chlorine four times forming NCl₄⁺ but phosphorus can bond with chlorine five times forming PCl₅. Explain.

 
 
 
 
 
 
 
 
 
 
 
 

6. 149) Constitutional isomers differ in the ___.

 
 
 
 

7. 150) Draw all the isomers of C₄H₉Br, using bond-line formulas.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

8. 153) Draw the Lewis structure of the nitrite ion, NO₂^– , clearly indicating resonance contributors as well as non-bonding pairs of electrons and formal charges, as relevant.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

9. Define an orbital.

 
 
 
 
 
 
 
 
 

10. There are three fundamental rules that we use in writing electronic configurations for atoms and molecules. The configuration shown below (for oxygen) violates one of these rules. Which one?

 
 
 
 
 
 
 
 
 
 
 
 
 
 

11. When atomic orbitals of opposite phase overlap a(n) ___ molecular orbital is formed.

 
 
 
 

12. The molecule N₂ does not show an absorption in an IR spectrum because the dipole moment of the molecule does not change with the absorption of IR energy.

 
 
 
 
 
 
 
 

13. Hydrocarbons containing carbon-carbon double bonds are referred to as ___.

 
 
 
 
 

14. All of the carbon-carbon bonds in ___ are equal to one and one-half bonds and have a bond length in between that of a single bond and a double bond with all of the bond angles at ___.

 
 
 
 
 

15. Unsaturated hydrocarbons may be distinguished from saturated hydrocarbons by the presence of one or more ___.

 
 
 
 

16. Draw all isomers of C₆H₁₄.

 
 
 
 
 
 
 
 
 
 
 
 
 

17. A polar covalent bond is one in which electrons are ___.

 
 
 
 
 
 
 

18. The ___ is defined as the product of the magnitude of the charge of a particle and the distance that separates them.

 
 

19. Carbon dioxide is non-polar, despite the fact that oxygen is much more electronegative than carbon. Briefly explain why, using relevant diagrams as appropriate to illustrate your answer.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

20. Nitromethane is a polar molecule but contains 2 equal polar covalent bonds. Briefly explain why and draw a relevant 3-dimensional structure to show the overall dipole moment of the molecule.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

21. Organic compounds are classified into chemical families on the basis of similarities in chemical properties; these similarities are primarily due to the presence of characteristic arrangements of atoms known as ___.

 
 
 
 
 
 

22. Draw all isomers of C₆H₁₂O that are aldehydes.

 
 
 
 
 
 
 
 
 
 
 

23. Draw all isomers of C₅H₁₀O that are ketones.

 
 
 
 
 
 
 
 
 
 
 
 

24. Draw all of the isomers of C₅H₉N that are nitriles.

 
 
 
 
 
 
 
 
 
 
 

25. Ethanol, C₂H₅OH, and propane, C₃H₈, have approximately the same molar mass, yet ethanol has a much higher boiling point. Briefly explain why.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

26. Ethanol, C₂H₅OH, and dimethyl ether, CH₃OCH₃, have the same molar mass, yet ethanol has a much higher boiling point. Briefly explain why.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

27. Sodium chloride, which is quite soluble in water, is not very soluble in hexane. Why?

 
 
 
 
 
 
 
 
 

28. Explain why the compound shown is considered to be capable of being a soap (dissolving oily substances off of surfaces using water).

 
 
 
 
 
 
 
 
 
 

29. Examine the following IR spectrum, for substance Q (C₇H₁₄O₂). Which oxygen containing functional group is most likely present in Q?

 
 
 
 
 
 
 
 
 
 
 

30. According to Bronsted-Lowry theory, an acid is a substance that can ___.

 
 
 
 

31. The molecule or ion that is formed when an acid loses its proton is called the ___.

 
 
 
 

32. When drawing mechanisms, chemists generally use curved arrows. The curved arrow begins at a(n) ___ rich area and points toward a(n) ___ deficient area.

 
 
 
 

33. According to Lewis theory, a base is a substance that can ___.

 
 
 
 

34. A substance that can donate a lone pair of electrons is a ___ according to ___ theory.

 
 
 
 

35. The isomer of alanine shown below is one of the 20 naturally occurring amino acids that are used to make proteins. Amino acids like alanine exist at neutral acidity (pH = 7) in the following form:

What would be the structure of alanine if HCl(aq) was added to lower the pH = 1? What would be the structure of alanine if NaOH(aq) was added until the pH = 12?
 
 
 
 
 
 
 
 
 
 

37. Write an equation to show the reaction between ethanol, C₂H₅OH and methyllithium, CH₃ Draw all non-bonding electrons and show electron flow with curved arrows.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

38. Write an equation that shows the reaction between acetic acid (CH₃COOH) and triethylamine (CH₃CH₂)₃ Draw all non-bonding lone electron pairs and show the electron flow with curved arrows.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

39. Why do water-insoluble carboxylic acids dissolve in aqueous sodium hydroxide?

 
 
 
 
 
 
 
 
 
 

40. Briefly, but clearly, explain why the –OH hydrogen in acetic acid (CH₃CO₂H) is more acidic than in ethanol (C₂H₅OH).

 
 
 
 
 
 
 
 
 

41. Define a protic solvent.

 
 
 
 
 
 
 

42. Draw an arrow pushing mechanism to illustrate the formation of t-butyl bromide from t-butanol and draw in the necessary intermediates and products formed.

 
 
 
 
 
 
 
 

43. You are planning to carry out a reaction between propyne, CH₃C≡CH and sodium amide, NaNH₂. You also need to choose an appropriate solvent for carrying out the reaction. Would ethanol be suitable for this purpose? Explain your rationale clearly.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Organic chemistry homework help