80 likes | 167 Views
Problems p.94 #32, 36, 38, 43, 45, 46, 49. 32. Is carbon dioxide gas a pure substance? Explain. Pure substance; constant composition. 36. List 3 states of matter, and give an example for each state. Differentiate between a gas and vapor. Solid Ex. Ice. 2. Liquid Ex. Water.
E N D
32. Is carbon dioxide gas a pure substance? Explain. • Pure substance; constant composition
36. List 3 states of matter, and give an example for each state. Differentiate between a gas and vapor. • Solid Ex. Ice 2. Liquid Ex. Water 3. Gas Ex. Helium • Substances that are in the gas phase at room temperature are referred to as gases, whereas substances such as water vapor that are not gases at room temperature are vapors.
38. Classify each as physical property or a chemical property.A. Al has a silvery color B. Au has a density of 19 g/cm3C. Na ignites when dropped in waterD. Water boils at 100oC E. Ag tarnishes F. Hg is a liquid at room temp A. physical B. physical C. chemical D. physical E. chemical F. physical
43. Classify each as a physical change or a chemical change.A. breaking a pencil in two B. water freezing and forming iceC. frying an eggD. burning woodE. leaves changing colors in the fall physical physical chemical chemical chemical
45. Is a change in phase a physical change or a chemical change? Explain. • It is a physical change. The composition of the substance does not change.
46. List 4 indicators that a chemical change has probably occurred. 1. Change in color 2. Change in temperature 3. Production of a gas upon mixing 4. Production of a solid upon mixing
49. Describe the difference between a physical change and a chemical change. • A physical change alters a substance without changing its composition, while a chemical change involves a change in composition.