HW matter 1.1-1.3

Seite 1

Hw 1.1-1.3

1. 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 close 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 evolved.

Answers

a. theory

b. Observation

c. Law

d. Observation

5. Classify each substance as a pure substance or a mixture. If it is a pure substance, classify it as an element or compound. If it is a mixture, classify it as homogeneous or heterogeneous.

a. sweat

b. carbon dioxide

c. aluminum

d. vegetable soup

Answers

a. mixture, homogeneous

b. pure substance, compound

c. pure substance, element

d. mixture, heterogeneous

7. Complete the table

Substance/Pure or Mixture/type

Aluminum, pure, element

Apple juice, mixture, homogeneous

hydrogen peroxide, pure, compound

chicken soup, mixture, heterogeneous

9. Determine whether each molecular diagram represents a pure substance or a mixture. If it represents a pure substance, classify it as an element or a compound. If it represents a mixture, classify it as homogeneous or heterogeneous.

a. pure substance, compound

b. mixture, heterogeneous

c. mixture homogeneous

d. pure substance, element