A chemist decomposes several samples of carbon monoxide into carbon and oxygen and weighs the resultant elements. The results are shown in the table. Do you notice a pattern in these results? Next, the chemist decomposes several samples of hydrogen peroxide into hydrogen and oxygen. The results are shown in the table. Do you notice a similarity between these results and those for carbon monoxide? Can you formulate a law from your observations? Can you formulate a hypothesis that might explain your law?

Classify each statement as an observation, a law, or a theory.

a. All matter is made of tiny, indestructible particles called atoms.

b. When iron rusts in a closed container, the mass of the container and its contents does not change.

c. In chemical reactions, matter is neither created nor destroyed.

d. When a match burns, heat is released

Classify each statement as an observation, a law, or a theory. a. Chlorine is a highly reactive gas. b. If elements are listed in order of increasing mass of their atoms, their chemical reactivities follow a repeating pattern. c. Neon is an inert (or nonreactive) gas. d. The reactivity of elements depends on the arrangement of their electrons.

Classify each substance as a pure substance or a mixture. If it is a pure substance, classify it as an element or a compound. If it is a mixture, classify it as homogeneous or heterogeneous. a. sweat b. carbon dioxide c. aluminum d. vegetable soup

Classify each substance as a pure substance or a mixture. If it is a pure substance, classify it as an element or a compound. If it is a mixture, classify it as homogeneous or heterogeneous. a. wine b. beef stew c. iron d. carbon monoxide