Chapter 1: Matter and Measurement 1. Which is not an example of a pure substance? A) Sugar B) Air C) Aluminum foil D) Water E) A block of dry ice Ans: B Difficulty: Easy 2. Which is an example of a physical change? A) The rusting of an iron nail B) The burning of propane in a gas grill C) Baking cookies D) Polishing tarnished silver E) Melting of an ice cube in a glass of soda Ans: E Difficulty: Easy 3. Which measurement has the fewest number of significant figures? A) 12.80 m B) 0.1280 m C) 0.001280 m D) 1280 m E) All of the measurements have the same number of significant figures. Ans: D Difficulty: Easy 4. Which quantity is an exact number? A) 3 cars B) 1,000 m C) 2 L D) 453.6 g Ans: A Difficulty: Easy 5. The number 0.0035880 expressed correctly using scientific notation is A) 0.0035889 D) 3.5880 × 10–3 B) 3.5880 × 10–4 E) 3.588 × 10–3 C) 3.5880 × 103 Ans: D Difficulty: Easy 6. The measurement 78,005,760 expressed correctly using scientific notation is A) 7.8005760 × 107 D) 7.800576 × 107 B) 7.800576 × 10–7 E) 7.8 × 107 C) 7.8005760 × 10–7 Ans: D Difficulty: Easy