Question

1. ab → a + b is a general notation for a(n) ________ reaction. a. anabolic b. endergonic c. decomposition d. exchange 17. ______ reactions release energy. a. catabolic b. exergonic c. decomposition d. catabolic, exergonic, and decomposition 18. which of the following combinations of atoms is most likely to result in a chemical reaction? a. hydrogen and hydrogen b. hydrogen and helium c. helium and helium d. neon and helium 19. chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. this is most likely due to the fact that ________. a. the inside of the mouth maintains a very high temperature b. chewing stores potential energy c. chewing facilitates synthesis reactions d. saliva contains enzymes

Explanation:

1. A decomposition reaction breaks a compound into simpler substances. Here, AB breaks into A and B.
2. Catabolic reactions break down molecules and release energy, exergonic reactions are energy - releasing, and decomposition reactions often release energy as bonds are broken.
3. Hydrogen is reactive and two hydrogen atoms can react to form hydrogen gas. Helium and neon are noble gases and are very stable and unreactive.
4. Saliva contains enzymes like amylase which facilitate the chemical breakdown of carbohydrates in bread.

Answer:

1. c. decomposition
2. d. Catabolic, exergonic, and decomposition
3. a. hydrogen and hydrogen
4. d. saliva contains enzymes