Ch 2 Study Guide

CH 2 study guide 1. Matter that always has exactly the same composition is classified as a(an) ____________________. 2. Pure substances are either ____________________ or ____________________. 3. An element has a fixed composition because it contains only one type of ____________________. 4. The symbols for elements have either ____________________ or ____________________ letters. 5. A compound can be made from two or more elements or __________ joined together in a fixed composition. 6. The substances in a(an) ____________________ mixture are evenly distributed throughout the mixture. 7. In a(an) ____________________ mixture, the parts of the mixture are noticeably different from one another. 8. Fresh milk is a suspension, but homogenized milk is a(an) ____________________. 9. If the particles in a mixture scatter light, the mixture is either a(an) ______________ or a(an) _________.

Figure 2-1 10. Look at Figure 2-1, the ______ point of nitrogen is 210.0ºC and the ______ point of nitrogen is 195.8ºC. 11. Measuring ____________________ can be used to test the purity of some substances. 12. If a spoon gets hot quickly when it is used to stir a pot of soup, it is probably made of __________. 13. A material used for electrical wiring would need to have good ____________________. 14. ___________ is a process that could be used to separated dissolved particles from the liquid in a solution. 15. ______ change occurs when a material changes shape but the composition of the material does not change. 16. ____________________ properties can be observed only when the substances in a sample of matter are changing into different substances. 17. Rust forms because iron and oxygen are highly ____________________ elements. 18. A solid that forms and separates from a liquid mixture is a(an) ____________________. 19. A cake rises as it bakes because a chemical change causes ____________________ to be produced. 20. How is the composition of a substance different from the composition of a mixture? 21. What is viscosity?

Figure 2-1 22. Based on the information in Figure 2-1, which substances would be solids at 110.0ºC? 23. How do changes in temperature usually affect the viscosity of a liquid? 24. What are three common clues that a chemical change has occurred? 25. How is a chemical change different from a physical change? USING SCIENCE SKILLS

Figure 2-2 26. Classifying Based on the data in Figure 2-2, is Mixture C a homogeneous or heterogeneous mixture? 27. Analyzing Data Which of the mixtures in Figure 2-2 is a solution? Explain how you know. 28. Analyzing Data Which of the mixtures in Figure 2-2 is a colloid? Explain how you know.

Figure 2-3 29. Use Figure 2-3 to compare the physical properties of clay before and after it is baked at a high temperature. 30. Using Tables and Graphs Which of the materials in Figure 2-3 are malleable? 31. Inferring You have an object made from one of the materials listed in Figure 2-3. It changes shape when you leave it in a sunny window. Which material is the object made from? How do you know?

32. Inferring Which of the materials described in Figure 2-3 would be least likely to be recycled? Explain your choice.