| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | calcium hydride | US | Used in chemistry labs and industrial processes for chemical reactions and as a drying agent. | 1 |
| 2 | calcium hypochlorite | United States | Calcium hypochlorite is commonly used as a swimming pool disinfectant in the United States and other western countries. | 1 |
| 3 | calcium hypochlorite | United States | Commonly used as a swimming pool disinfectant | 1 |
| 4 | calcium hypochlorite | United States | Commonly used as a chemical for water treatment and disinfection, especially in swimming pools and spa systems. | 1 |
| 5 | water hyacinth | United States | Invasive aquatic plant causing ecological problems in water bodies | 1 |