chemistry

2. (of a reaction or process) accompanied by the release of heat.
4. a gas that contributes to the greenhouse effect by absorbing infrared radiation, e.g., carbon dioxide and chlorofluorocarbons.
6. a metal made by combining two or more metallic elements
7. (of a reaction or process) accompanied by or requiring the absorption of heat.
9. a substance used for destroying insects or other organisms harmful to cultivated plants or to animals.
10. a broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms
12. a reaction where an acid reacts with an alkali to form a neutral solution of a salt and water
13. the process of corroding metal, stone, or other materials.
15. a substance that is toxic to plants, used to destroy unwanted vegetation.
16. canada's national hazard communication standard

1. a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.
3. a substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together
5. a material or chemical, especially a textile fiber.
8. a change apparent from the mid to late 20th century onwards and attributed largely to the increased levels of atmospheric carbon dioxide produced by the use of fossil fuels.
11. the process of burning something.
14. an apparatus using water or a solution for purifying gases or vapors.