Rank The Following Compounds In Order Of Increasing Boiling Point.

Boiling Point Enigma: Unraveling the Factors that Govern Compound Behavior

In the realm of chemistry, understanding the properties of compounds is crucial for a wide range of applications. Among these properties, boiling point plays a significant role in various processes, such as distillation, evaporation, and temperature control. Delving into the factors that influence the boiling points of compounds can provide valuable insights and practical implications.

Boiling Points: A Reflection of Intermolecular Forces and Molecular Structure

The boiling point of a compound is the temperature at which it transitions from a liquid to a gas. This phenomenon is governed by the strength of intermolecular forces, which are the attractive forces between molecules. Stronger intermolecular forces require more energy to overcome, resulting in higher boiling points. Additionally, molecular structure also impacts boiling points, with larger and more complex molecules generally having higher boiling points.

Ranking Compounds by Increasing Boiling Points

To rank compounds in order of increasing boiling points, we need to consider the intermolecular forces and molecular structures of each compound. Here’s a closer look at how these factors influence boiling points:

  • Nonpolar Compounds: Nonpolar compounds, such as alkanes, have weak intermolecular forces (van der Waals forces) due to the absence of polarity. As a result, they have relatively low boiling points.
  • Polar Compounds: Polar compounds, such as alcohols and ketones, have stronger intermolecular forces (dipole-dipole interactions) due to the presence of polar bonds. These stronger forces lead to higher boiling points compared to nonpolar compounds.
  • Hydrogen Bonding: Hydrogen bonding is a particularly strong type of dipole-dipole interaction that occurs between hydrogen atoms bonded to highly electronegative atoms like oxygen, nitrogen, and fluorine. Compounds capable of forming hydrogen bonds, such as water and alcohols, have significantly higher boiling points than similar compounds that lack hydrogen bonding.
  • Molecular Structure: Larger and more complex molecules generally have higher boiling points due to increased surface area and stronger intermolecular forces. This is because larger molecules have more electrons, leading to stronger van der Waals forces and dipole-dipole interactions.

Boiling Points: A Window into Molecular Characteristics

In essence, ranking compounds in order of increasing boiling points provides insights into their intermolecular forces and molecular structures. This information is valuable for predicting compound behavior in various applications. For instance, higher boiling point compounds are more difficult to vaporize, making them suitable for use as solvents or heat transfer fluids. Understanding boiling points also aids in the design and optimization of processes involving phase transitions.

Rank The Following Compounds In Order Of Increasing Boiling Point.

Rank the Following Compounds in Order of Increasing Boiling Point


In chemistry, the boiling point of a compound is the temperature at which the liquid phase of the compound transforms into the gas phase. This phenomenon is characterized by the formation of bubbles within the liquid, which then rise to the surface and burst, releasing vapor. The boiling point of a compound is influenced by various factors, including its molecular structure, intermolecular forces, and the strength of these forces.

Factors Affecting Boiling Point:

  1. Molecular Weight: Generally, compounds with higher molecular weights have higher boiling points.

  2. Intermolecular Forces: The strength of intermolecular forces also plays a crucial role in determining the boiling point. Stronger intermolecular forces, such as hydrogen bonding, dipole-dipole interactions, and London dispersion forces, require more energy to overcome, resulting in higher boiling points.

  3. Molecular Structure: The shape and geometry of molecules can also influence their boiling points. For instance, branched molecules tend to have lower boiling points compared to their linear counterparts due to weaker intermolecular forces.

Ranking Compounds by Increasing Boiling Point:

  1. Ethane (CH3CH3):
  • Image:
    Ethane Molecule
  • Boiling Point: -88.6°C
  • Ethane is a simple hydrocarbon with a low molecular weight and weak intermolecular forces (London dispersion forces).
  1. Methanol (CH3OH):
  • Image:
    Methanol Molecule
  • Boiling Point: 64.7°C
  • Methanol possesses a hydroxyl group (-OH), which enables hydrogen bonding, resulting in stronger intermolecular forces compared to ethane.
  1. Acetone ((CH3)2CO):
  • Image:
    Acetone Molecule
  • Boiling Point: 56.2°C
  • Acetone has a carbonyl group (C=O), which allows for dipole-dipole interactions. Additionally, its molecular weight is slightly higher than that of methanol.
  1. 1-Butanol (CH3(CH2)3OH):
  • Image:
    1-Butanol Molecule
  • Boiling Point: 117.7°C
  • 1-Butanol has a longer carbon chain compared to methanol and acetone, resulting in stronger London dispersion forces. The presence of the hydroxyl group also contributes to hydrogen bonding.
  1. Water (H2O):
  • Image:
    Water Molecule
  • Boiling Point: 100°C
  • Water exhibits exceptionally strong hydrogen bonding due to its unique molecular structure. These hydrogen bonds require a substantial amount of energy to break, leading to water’s relatively high boiling point.


The boiling points of compounds are determined by various factors, including molecular weight, intermolecular forces, and molecular structure. By understanding these factors, we can predict and rank the boiling points of different compounds. This knowledge is crucial in various scientific and industrial applications, such as distillation, evaporation, and temperature control.


  1. Q: Why does water have a higher boiling point than ethanol?
    A: Water molecules engage in stronger hydrogen bonding compared to ethanol molecules. This results in a higher boiling point for water.

  2. Q: How does branching affect the boiling point of hydrocarbons?
    A: Branching in hydrocarbon molecules leads to a decrease in intermolecular forces, resulting in lower boiling points.

  3. Q: What is the relationship between molecular weight and boiling point?
    A: In general, compounds with higher molecular weights tend to have higher boiling points.

  4. Q: Can intermolecular forces be influenced to alter the boiling point of a compound?
    A: Yes, modifying intermolecular forces, such as through the addition of impurities or by changing the temperature and pressure, can affect the boiling point of a compound.

  5. Q: What are some practical applications of understanding boiling points?
    A: Boiling points are used in various applications, including distillation, evaporation, temperature control, and the design of chemical processes.



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