Chemical Species/Chemical Interactions:
1. State whether each solid is molecular, atomic, or ionic.
a.) Cu(s)
b.) H2O(s)
c.) NaCl(s)
d.) Fe(s)
2. What is a molecular solid? What makes it different than an atomic or ionic solid?
3. If you were to mix CH3CH2OH with H2O, would this mixture be miscible or immiscible? Why?
4. If you were to mix CH3CH2CH2CH3 with H2O, would this mixture be miscible or immiscible? Why?
5. Define a homogeneous mixture.
6. Determine whether a homogeneous mixture will form when each pair of substances interacts:
a.) H2O and CH3CH2CH3
b.) CH3OH and CH3CH2OH
c.) CH3CH2CH3 and CH3CH2CH2CH3
Intermolecular Forces:
7. Identify the strongest intermolecular force present in each of the species:
a.) CH4
b.) HF
c.) H2O
d.) CHCl3
8. What intermolecular force do ALL species have?
9. List ALL of the intermolecular forces present in the following molecules:
a.) CH3CH2OH
b.) CCl4
c.) CHF3
10. Identify the strongest intermolecular force in each molecule:
a.) NH3
b.) HCl
11. Under what circumstances is a hydrogen-bond present?
12. Identify the strongest intermolecular force present in the following molecules:
a.) CO2
b.) O2
c.) Ni
d.) CH3CHO2
13. List the following molecules in order of increasing dominant intermolecular force:
HF, CH4, CH3CHO2
14. List the following molecules in order of decreasing dominant intermolecular force:
NH3 , CH3CH2CH3 , HCl
15. List all of the intermolecular forces in the following substances:
a.) CO
b.) HBr
c.) CCl4
d.) KCl
16. Identify the dominant intermolecular force in the following substances:
a.) N2H2
b.) SO
c.) CH4O
d.) BH3
17. Circle the correct dominant intermolecular force for: NH2CH3 **Hint: Drawing the Lewis Structure may be helpful**
a.) Dispersion
b.) Dipole-Dipole
c.) H-Bond
18. Circle all intermolecular forces that silicon tetrabromide has:
a.) Dispersion
b.) Dipole-Dipole
c.) H-Bond
19. What is the dominant intermolecular force in each of the following molecules?
a.) ammonia
b.) silicon dioxide
c.) ethanol
d.) acetic acid
20. List all of the intermolecular forces present in each of the following substances:
a.) copper (s)
b.) phosphoric acid
c.) selenium difluoride
d.) butane
21. Circle the dominant intermolecular force for the compound: CH3OCH3
a.) Dispersion
b.) Dipole-Dipole
c.) H-Bond
22. All of the following molecules have hydrogen-bonding forces, EXCEPT…
a.) HF
b.) HCl
c.) H2O
d.) NH3
23. All of the following molecules have dipole-dipole forces, EXCEPT…
a.) CH4
b.) CH3OCH2CH3
c.) CH3OCH3
d.) HF
24. All of the following molecules have dispersion forces as their DOMINANT intermolecular force, EXCEPT…
a.) CF4
b.) CCl4
c.) CH3CH2CH2CH2CH3
d.) CH2Cl2
25. List the dominant intermolecular forces for the following substances:
a.) I2
b.) F2
c.) SO2
d.) HCH3COO
Boiling/Melting Point:
26. By looking at the Lewis structures of different molecules, how would you know which molecule has the higher boiling point?
27. If you are given the formula of different molecules, how would you know which molecule has the higher boiling point?
28. Circle which molecule will has the higher boiling point:
a.) CH4
b.) CH3CH3
29. Given the following substances, list them in order of decreasing boiling point:
NaCl, CH3CH2OH, Ar, CHCl3
30. When given two molecules, how would you know which substance is a liquid at room temperature?
31. At room temperature, CO2 is in its gas form, while CH3OH is in its liquid form. Explain why.
32. List the following noble gases in order of increasing boiling point:
Kr, He, Ar, Xe, Rn, Ne
33. When comparing NaCl and CH4, which molecule has the higher melting point?
34. When comparing solid CO2 with solid SO2, which one will have the higher melting point? Why?
35. Circle the molecule with the highest melting point:
a.) NH4Cl
b.) CH3OH
c.) HF
36. Circle the molecule with the highest boiling point:
a.) CH3CH2CH2CH2CH3
b.) CH3CH2CH2CH2CH2CH2CH3
c.) CH3CH3
37. Circle the molecule with the lowest boiling point:
a.) CH3OCH3
b.) CH3CH2CH3
c.) CH4
38. Determine which molecule has the higher boiling point.
a.) methanol
b.) carbon dioxide
39. Determine which molecule has the higher boiling point.
a.) H2
b.) HCl
40. Which substance has the lowest boiling point?
a.) H2O
b.) Ne
c.) NH3
d.) NaF
41. Arrange the list of acids in order of highest to lowest melting point.
HCl, HI, HBr
42. Compare H2O(s) and H2S(s). Which molecule has the higher melting point? Why?
43. Arrange the molecules in order of decreasing boiling point:
Hexane (C6H14), Octane (C8H18), Butane (C4H10)
44. From the choices below, which one has the lowest boiling point?
a.) C5H12
b.) C10H22
c.) C2H2
45. Ethanol (CH3CH2OH) and propane (C5H12) have similar molar masses. Does that mean they have the same boiling point? Explain.
46. For each of the pairs below, circle the substance with the higher boiling point:
a.) I2 and F2
b.) HF and LiF
c.) CH2O2 and CCl4
47. For each of the pairs below, circle the substance with the higher boiling point:
a.) propanol and methanol
b.) methane and pentane
c.) dihydrogen monoxide and dihydrogen monosulfide
48. Arrange the following substances in order of increasing boiling points:
acetic acid (CH3COOH), acetone (C3H6O), water (H2O)
49. Which substance would most likely be a liquid at room temperature, CH3COOH or CCl4?
50. From the following molecules, which one has the highest boiling point? Which one has the lowest boiling point?
a.) CH3CH2CH2CH3
b.) CH3CH2CH2CH2CH2CH2CH2CH3
c.) CH3CH2CH3
d.) CH3CH2CH2CH2CH2CH3
51. For the pair below, which one has the higher boiling point? Explain.
CH3CH2COH or CH3CH3
52. From the following molecules, which one has the higher boiling point?
a.) CH3CH2CH2COH
b.) CH3CH2CH2CH3
c.) CH4
53. From the following molecules, which one has the lowest boiling point?
a.) CH3CH2CH2CH3
b.) CH4
c.) CO2
Cumulative/Challenge Problems:
54. Why are hydrogen-bonding forces unusually stronger than the average dipole-dipole force?
55. The Lewis structure for acetone is provided below. Can a hydrogen-bond form if two acetone molecules were allowed to bond together? Explain.
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56. Could a water molecule form a hydrogen bond with an acetone molecule? Explain. (The Lewis structure provided in the previous problem may be helpful).
57. Circle the choice that is a homogeneous mixture:
a.) orange juice with pulp
b.) vinegar
c.) bowl of cereal
d.) vegetable soup
58. The Lewis structures for butane and iso-butane are provided below. Which molecule will have the higher boiling point? Do they have the same boiling point because each molecule has the same amount of carbons and hydrogens? Explain.
59. Determine the dominant intermolecular forces for each of the following molecules: **Hint: use the Lewis structures provided in the previous problems for extra help.**
a.) acetone
b.) butane
c.) iso-butane
60. Determine all of the intermolecular forces present in each of the following substances:
a.) nitric acid
b.) benzene
c.) ethanol