AP Cemistry Homework Cpt 1 Answers.doc

AP Chemistry Homework Chapter 1: 1. Identify each of the following substances as a gas, a liquid, or a solid under ordinary conditions of temperature and pressure: (a) mercury, (b) sodium bicarbonate (baking soda), (c) hydrogen, (d) carbon monoxide, (e) oxygen, (f) isopropyl alcohol, (g) sodium chloride. Ans: L;S;G;G 2. Indicate which of the following are physical processes and which are chemical processes: (a) corrosion of aluminum metal, (b) cutting a diamond, (c) burning gasoline, (d) boiling water. Ans: C;P;C;P 3. A match is lit and held under a cold piece of metal. The following observations are made: (a) The match burns. (b) The metal gets warmer. (c) Water condenses on the metal. (d) Soot (carbon) is deposited on the metal. Which of these occurrences are due to physical changes and which are due to chemical changes? Ans: C;P;C;C; 4. In the process of attempting to characterize a substance, a chemist makes the following observations: The substance is a silvery-white, lustrous metal. It melts at 6490C and boils at 11050C. Its density at 200C is 1.738g/cm3. The substance burns in air, producing an intense white light. It reacts with chlorine to give a brittle, white solid. The substance can be pounded into thin sheets or drawn into wires. It is a good conductor of electricity. Which of these characteristics are physical properties and which are chemical properties? Ans: chemical – burns to produce white light and reacts with Cl to produce a white solid 5. Classify the following observations about a substance as either physical or chemical properties: (a) color, (b) melting point, (c) reactivity with water, (d) boiling point, (e) state of matter under ordinary conditions, (f) flammability, (g) density, (h) electrical conductivity, (i) decomposition products upon heating. Ans: P;P;C;P;P;C;P;P;C 6. Classify the following as a pure substance or a mixture; i