Portable radios didn't use chemical energy directly to produce sounds. They used batteries which store chemical energy and convert it to electrical energy. This electrical energy then powers the radio receiver which picks up radio waves.

Here's a breakdown:

* Chemical Energy: Stored in the batteries.

* Electrical Energy: Converted from chemical energy by the batteries.

* Radio Receiver: Uses the electrical energy to amplify and decode radio waves.

* Speaker: Converts the electrical signals from the radio receiver into sound waves.

Therefore, while chemical energy is the initial source, the actual sound production is a result of electrical energy powering the radio receiver and speaker.