All Flashcards

What are the steps to calculate $\Delta H$ using BDEs?

Break all bonds in reactants. 2. Form all bonds in products. 3. Sum BDEs of bonds broken. 4. Sum BDEs of bonds formed. 5. Apply the formula: $\Delta H = \Sigma H(broken) - \Sigma H(formed)$ .

Compare the energy changes in breaking vs. forming bonds.

Breaking bonds: requires energy (endothermic). Forming bonds: releases energy (exothermic).

How do bond length and bond strength relate to BDE?

Shorter bonds: stronger, higher BDE. Longer bonds: weaker, lower BDE.

Differentiate between single, double, and triple bonds in terms of BDE.

Single bonds: lowest BDE. Double bonds: intermediate BDE. Triple bonds: highest BDE.

What is the effect of increasing bond order on bond strength?

Increasing bond order (single to double to triple) increases bond strength.

What is the effect of a negative $\Delta H$ value?

The reaction is exothermic, meaning it releases heat.

What is the effect of a positive $\Delta H$ value?

The reaction is endothermic, meaning it requires heat.