Batteries were invented in 1800, but their complex chemical processes are still being explored and improved. While there are several types of batteries, at its essence a battery is a device that converts chemical energy into electric energy.

Climate science, or climatology, is the study of Earth’s climate. Climate scientists want to better understand our planet’s atmosphere and how it affects various ecosystems. Many equate climate with the weather. And indeed, the word climate is usually defined as the average weather conditions in a particular area over a long-term period, such as years or decades. But climate science touches far more than weather trends.

Fentanyl analogs are illicit—and often deadly—alterations of the medically prescribed drug fentanyl. The analogs have similar—but not the same—chemical structure, and they mimic the pharmacological effects of the original drug.