Chemistry: Bond Dissociation Enthalpy

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the definition of bond dissociation enthalpy?

Energy released when forming one mole of gaseous bonds.
Energy required to break one mole of gaseous bonds to form gaseous atoms. (correct)
Energy needed to form diatomic molecules from gaseous atoms.
Energy required to break one mole of liquid bonds.

What characterizes the process of breaking a chemical bond?

Energy must be supplied to the system. (correct)
It does not involve any changes in energy.
It occurs spontaneously without energy input.
It is an exothermic process.

How is the bond enthalpy related to the strength of a bond?

Bond enthalpy has no relationship to bond strength.
Lower bond enthalpy implies a stronger bond.
Higher bond enthalpy indicates a weaker bond.
Higher bond enthalpy correlates with a stronger bond. (correct)

What statement regarding bond enthalpy and diatomic gases is true?

The bond enthalpy is twice the enthalpy of atomization. (D) Signup and view all the answers

What happens during the process of bond formation?

Energy is released to the surroundings. (A) Signup and view all the answers

What is true regarding the energy involved in breaking a chemical bond?

Energy is required to break any chemical bond. (C) Signup and view all the answers

How does bond enthalpy relate to bond strength?

Higher bond enthalpy indicates a stronger bond. (D) Signup and view all the answers

What happens during the exothermic process of bond formation?

Atoms lose energy when bonds are formed. (D) Signup and view all the answers

Which statement is correct regarding bond dissociation enthalpy for diatomic gases?

It equals the enthalpy of atomization for the gas's individual atoms. (C) Signup and view all the answers

What can be inferred about a bond with a small bond dissociation enthalpy?

The bond is likely to be weak and easily breakable. (C) Signup and view all the answers

Flashcards

Bond Dissociation Enthalpy

The amount of energy required to break one mole of a specific bond in a gaseous molecule, resulting in individual gaseous atoms.

Breaking bonds and endothermic reactions

The process of breaking a bond always requires absorption of energy, making it an endothermic process.

Forming bonds and exothermic reactions

The process of forming a new bond always releases energy, making it an exothermic process. This is the opposite of breaking a bond.

Average bond enthalpy

Since bond strength varies based on factors like the molecule's environment, quoted values typically represent average bond enthalpies.

Signup and view all the flashcards

Bond enthalpy and atomization

For diatomic molecules, the bond enthalpy is double the enthalpy of atomization. This means the energy required to break the bond is twice the energy needed to separate one mole of the diatomic molecule into individual atoms.

Signup and view all the flashcards

Bond Dissociation Enthalpy (BDE)

The energy needed to break one mole of a specific type of bond in a gaseous molecule, forming individual gaseous atoms.

Signup and view all the flashcards

Study Notes

Bond Dissociation Enthalpy Definition

Bond dissociation enthalpy (energy) is the energy required to break one mole of gaseous bonds to form gaseous atoms.

Key Characteristics

Endothermic Process: Breaking a chemical bond requires energy input.
Bond Strength Variation: Bond strength varies depending on the surrounding atoms/molecules; thus, average values are used.
Making Bonds is Exothermic: Forming a bond releases energy, the opposite of breaking a bond.
Diatomic Gases: For diatomic gases, bond enthalpy is twice the enthalpy of atomisation.
Bond Strength Correlation: Smaller bond enthalpy indicates a weaker bond, making it easier to break.
Values: Bond dissociation enthalpy values are endothermic. Energy must be input to break any chemical bond. For example, breaking Cl₂ (g) into 2Cl (g) requires energy input.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the fundamental concepts of bond dissociation enthalpy, including its definition, characteristics, and the energy requirements for breaking chemical bonds. Understand the differences between endothermic and exothermic processes and how bond strengths vary among different molecules.