For Each Pair Of Compounds Listed, Check The Box Next To The One With The Higher Boiling Point.$[ \begin{tabular}{|c|c|} \hline \text{Compounds} & \text{Higher Boiling Point} \ \hline SiH_4 & \ SiCl_4 & \ \hline Si_4H_{10} & \ Si_3H_8 &

Introduction

In chemistry, the boiling point of a compound is a critical property that determines its physical state at a given temperature. It is the temperature at which a substance changes state from a liquid to a gas. The boiling point of a compound is influenced by the strength of the intermolecular forces between its molecules. In this article, we will explore the concept of boiling points and how to determine the compound with the higher boiling point in a given pair.

Intermolecular Forces and Boiling Points

Intermolecular forces are the attractive and repulsive forces between molecules. These forces play a crucial role in determining the boiling point of a compound. The stronger the intermolecular forces, the higher the boiling point of the compound. There are several types of intermolecular forces, including:

• London Dispersion Forces: These are weak intermolecular forces that arise due to temporary dipoles in nonpolar molecules.
• Dipole-Dipole Forces: These are intermolecular forces that arise due to the attraction between two polar molecules.
• Hydrogen Bonding: This is a type of intermolecular force that arises due to the attraction between a hydrogen atom bonded to a highly electronegative atom and another electronegative atom.

Determining Higher Boiling Points

To determine the compound with the higher boiling point in a given pair, we need to analyze the intermolecular forces present in each compound. Let's consider the following pairs of compounds:

SiH4 vs SiCl4

SiH4 (silane) and SiCl4 (silicon tetrachloride) are both silicon-based compounds. However, they differ in their molecular structure and intermolecular forces.

• SiH4: SiH4 is a nonpolar molecule with a tetrahedral molecular structure. The intermolecular forces present in SiH4 are London dispersion forces.
• SiCl4: SiCl4 is a polar molecule with a tetrahedral molecular structure. The intermolecular forces present in SiCl4 are dipole-dipole forces.

Since dipole-dipole forces are stronger than London dispersion forces, SiCl4 has a higher boiling point than SiH4.

Si4H10 vs Si3H8

Si4H10 (silane) and Si3H8 (silane) are both silicon-based compounds. However, they differ in their molecular structure and intermolecular forces.

• Si4H10: Si4H10 is a nonpolar molecule with a tetrahedral molecular structure. The intermolecular forces present in Si4H10 are London dispersion forces.
• Si3H8: Si3H8 is a nonpolar molecule with a tetrahedral molecular structure. The intermolecular forces present in Si3H8 are London dispersion forces.

Since both compounds have the same type of intermolecular forces, we need to consider the molecular weight of each compound. The compound with the higher molecular weight will have a higher boiling point. Si4H10 has a higher molecular weight than Si3H8, so Si4H10 has a higher boiling point than Si3H8.

Conclusion

In conclusion, the boiling point of a compound is influenced by the strength of the intermolecular forces between its molecules. By analyzing the intermolecular forces present in each compound, we can determine the compound with the higher boiling point in a given pair. In this article, we have considered two pairs of compounds and determined the compound with the higher boiling point in each pair.

References

• Kittel, C. (2005). Introduction to Solid State Physics. John Wiley & Sons.
• Atkins, P. W. (2007). Physical Chemistry. Oxford University Press.
• Moore, J. W. (2008). Physical Chemistry. Pearson Education.

Discussion

• What are the intermolecular forces present in SiH4 and SiCl4?
• Why does SiCl4 have a higher boiling point than SiH4?
• What are the intermolecular forces present in Si4H10 and Si3H8?
• Why does Si4H10 have a higher boiling point than Si3H8?

Answer Key

• SiH4: London dispersion forces
• SiCl4: Dipole-dipole forces
• Si4H10: London dispersion forces
• Si3H8: London dispersion forces

Higher Boiling Point

Introduction

In our previous article, we discussed the concept of boiling points and how to determine the compound with the higher boiling point in a given pair. In this article, we will answer some frequently asked questions related to determining higher boiling points in compounds.

Q1: What are the factors that affect the boiling point of a compound?

A1: The boiling point of a compound is affected by the strength of the intermolecular forces between its molecules. The stronger the intermolecular forces, the higher the boiling point of the compound. The factors that affect the boiling point of a compound include:

• Molecular weight: The higher the molecular weight of a compound, the higher its boiling point.
• Intermolecular forces: The strength of the intermolecular forces between molecules affects the boiling point of a compound.
• Polarity: Polar compounds have stronger intermolecular forces than nonpolar compounds, resulting in higher boiling points.

Q2: How do I determine the intermolecular forces present in a compound?

A2: To determine the intermolecular forces present in a compound, you need to analyze its molecular structure and properties. The following are some ways to determine the intermolecular forces present in a compound:

• Molecular structure: The molecular structure of a compound can indicate the presence of intermolecular forces. For example, polar molecules have dipole-dipole forces, while nonpolar molecules have London dispersion forces.
• Polarity: The polarity of a compound can indicate the presence of dipole-dipole forces.
• Molecular weight: The molecular weight of a compound can indicate the presence of London dispersion forces.

Q3: How do I determine the boiling point of a compound?

A3: To determine the boiling point of a compound, you need to analyze its intermolecular forces and molecular weight. The following are some steps to determine the boiling point of a compound:

• Analyze the molecular structure: Determine the molecular structure of the compound and identify the presence of intermolecular forces.
• Determine the intermolecular forces: Determine the type of intermolecular forces present in the compound.
• Calculate the boiling point: Use the strength of the intermolecular forces and the molecular weight of the compound to calculate its boiling point.

Q4: What are some common mistakes to avoid when determining the boiling point of a compound?

A4: Some common mistakes to avoid when determining the boiling point of a compound include:

• Ignoring the molecular weight: Molecular weight is an important factor in determining the boiling point of a compound.
• Not considering the intermolecular forces: The strength of the intermolecular forces between molecules affects the boiling point of a compound.
• Not analyzing the molecular structure: The molecular structure of a compound can indicate the presence of intermolecular forces.

Q5: How do I apply the knowledge of boiling points to real-world scenarios?

A5: The knowledge of boiling points can be applied to real-world scenarios in various ways, including:

• Chemical engineering: Boiling points are critical in chemical engineering, where they are used to design and optimize chemical processes.
• Materials science: Boiling points are used to determine the properties of materials, such as their melting and boiling points.
• Pharmaceuticals: Boiling points are used to determine the properties of pharmaceutical compounds, such as their melting and boiling points.

Conclusion

In conclusion, determining the boiling point of a compound requires a thorough understanding of the intermolecular forces and molecular weight of the compound. By analyzing the molecular structure and properties of a compound, you can determine the boiling point of the compound. This knowledge can be applied to real-world scenarios in various fields, including chemical engineering, materials science, and pharmaceuticals.

References

• Kittel, C. (2005). Introduction to Solid State Physics. John Wiley & Sons.
• Atkins, P. W. (2007). Physical Chemistry. Oxford University Press.
• Moore, J. W. (2008). Physical Chemistry. Pearson Education.

Discussion

• What are some common mistakes to avoid when determining the boiling point of a compound?
• How do I apply the knowledge of boiling points to real-world scenarios?
• What are some real-world applications of boiling points?

Answer Key

• Q1: Molecular weight, intermolecular forces, and polarity.
• Q2: Molecular structure, polarity, and molecular weight.
• Q3: Analyze the molecular structure, determine the intermolecular forces, and calculate the boiling point.
• Q4: Ignoring the molecular weight, not considering the intermolecular forces, and not analyzing the molecular structure.
• Q5: Chemical engineering, materials science, and pharmaceuticals.