When propane (C_3H_8) burns in air, which form of energy is primarily converted to thermal energy?

• A. Electrical energy
• B. Nuclear energy
• C. Chemical energy
• D. Radiant energy

Answer: (C)

Verified step by step guidance

1. Identify the type of reaction occurring: the combustion of propane (C\_3H\_8) is a chemical reaction where propane reacts with oxygen to form carbon dioxide and water.
2. Understand that during combustion, the chemical bonds in propane and oxygen molecules are broken and new bonds are formed in the products, releasing energy.
3. Recognize that the energy released during this process originates from the chemical potential energy stored in the bonds of the reactants.
4. Note that this released energy is primarily converted into thermal energy (heat), which is why combustion reactions are exothermic and produce heat.
5. Conclude that the form of energy converted to thermal energy in the combustion of propane is chemical energy.