When a car burns gasoline with air to produce heat, where does most of the energy released come from?

• A. The conversion of kinetic energy to potential energy
• B. The formation of new chemical bonds in the combustion products
• C. The absorption of heat from the surroundings
• D. The breaking of chemical bonds in gasoline molecules

Answer: (B)

Verified step by step guidance

1. Understand that in a chemical reaction, energy changes occur due to the breaking and forming of chemical bonds.
2. Recall that breaking chemical bonds requires energy input (endothermic process), while forming new chemical bonds releases energy (exothermic process).
3. In combustion, gasoline molecules react with oxygen, breaking bonds in the reactants and forming new bonds in the products such as CO2 and H2O.
4. Recognize that the net energy released (heat) during combustion primarily comes from the energy released when new, more stable chemical bonds are formed in the combustion products.
5. Therefore, the majority of the energy released in burning gasoline comes from the formation of new chemical bonds in the combustion products, not from breaking bonds or other processes.