Season 1 · Episode 2
Dr Stone · S1E2
Aired on July 12, 2019
Science entries in this episode
Calcium Carbonate
Senku presents calcium carbonate as civilization's cornerstone: we explain CaCO₃, the lime cycle, and its uses in agriculture and construction.
Food Smoking
Tsukasa smokes his meat in Dr Stone: we explain the chemistry of smoke, the role of aldehydes and phenols, and the modern health risks.
Lime Mortar
Senku proposes building with mortar: we explain the chemistry of hydraulic set, the secret of Roman concrete, and the shift to modern lime.
Sodium Carbonate
Senku mentions seaweed-derived sodium carbonate as a soap ingredient: we explain the chemistry of Na₂CO₃, its natural sources, and its shift to industry.
Also mentioned in this episode
Topics raised without enough material for a dedicated entry, listed here for editorial transparency. They will be expanded when the manga or anime returns to them in more depth.
- Food chain and apex predator ⏱ 06:55–07:01
An isolated line about being an apex predator at the top of the food chain in the petrified world. The concept is mentioned without any elaboration.
- Ebola virus ⏱ 10:54–10:58
Brief biographical reference to Senku's scientific background (an interest in virology, the Ebola virus). No scientific explanation is developed by the episode.