Chemistry doesn’t just shape conflict — conflict shapes chemistry. And at no time in history is that more apparent than during the two world wars. Historian Alison McManus recounts how the race to weaponize toxic gases like chlorine and mustard gas transformed chemists into key military players, spurred industrial growth, and ignited an international arms race during WWI.

However, some battles of the world wars weren’t waged against an opposing army, but against diseases that soldiers caught while in combat. Journalist Karen Masterson reveals how WWII triggered a massive scientific mobilization — a secret, high‑stakes search for synthetic quinine and antimalarial drugs that would ultimately help seed the modern pharmaceutical industry. Packed with espionage, innovation, and ethical dilemmas, this episode uncovers how war accelerated chemistry in ways that still shape science today.

Transcripts at acs.org/chainreaction

In this debut episode of Chain Reaction, we go on a thrilling journey through the earliest chapters of chemistry’s history starting with the quest to make gold from abundant metals. Chemical historian Larry Principe guides us through the winding past of alchemy – its evolution across Greek, Islamic, and European traditions, and the secrecy, symbolism, and ambition that defined the craft. From coded manuscripts to the social politics that ultimately pushed alchemy underground, Larry reveals how hands-on experimentation shaped the scientific mindset we now take for granted.

Then the episode fast-forwards through centuries of discovery – from identifying elements, to early gas experiments, to the birth of the periodic table, to the atomic revolution – guided by science writers Sam Kean and Cathy Cobb. It’s a whirlwind introduction to how humans learned to understand, categorize, and ultimately master matter.

Transcripts at acs.org/chainreaction

Introducing Chain Reaction, a podcast by the American Chemical Society that links chemistry's past to its future, revealing how this ever‑evolving science shapes the world around us — from the materials we use every day to the environment that we depend on. Each episode brings fresh perspectives and personal stories from chemists, engineers, and other scientists, as well as historians who guide us through pivotal moments in chemistry’s history. Together, we’ll uncover chemistry’s surprising connections, explore its interdisciplinary impact, and see how past discoveries set off the breakthroughs of today and the future. Whether you’re a student, an experienced scientist, or simply curious, Chain Reaction will show you how chemistry fits into the bigger picture — and why it matters now more than ever.

Transcripts at acs.org/chainreaction