Transcript Week 7
Week 7 1. A student made a solution by dissolving sugar in tap water. She wanted to increase the concentration of her sugar solution. Select the best way for her to do that. a. b. c. d. Add more sugar to the existing solution Add more water to the existing solution Warm the solution Agitate the solution 2. Which of the following substances is acidic? A. B. C. D. Liquid soap Vinegar Baking soda Flour 3. Carbon dioxide in the atmosphere reacts with rainwater to form carbonic acid. The pH of this rainwater is A. B. C. D. Less than 7. 7. Greater than 7. Not measurable by ordinary means. 4. The picture below shows a carbonated beverage. Which term describes the CO2 gas? A. B. C. D. Ion Element Solute Solvent 5. A student is investigating a sample of an element. The student observes that the element is solid, shiny, and can be bent into a new shape. The student is most likely observing a. b. c. d. Carbon. Oxygen. Hydrogen. Aluminum. 6. Which of the following is a true statement? a. b. c. d. Matter is conserved in a chemical reaction. Matter is created in a chemical reaction. Matter is destroyed in a chemical reaction. All of the above statements can be true depending on the reaction. 7. What happens to the temperature of a solid as it melts? a. b. c. d. It stays the same. It increases. It decreases. It increases and then decreases. 8. The melting and boiling points of silver are respectively 960.8 degrees Celsius and 1950 degrees Celsius. What is its freezing point? a. b. c. d. 0 degrees C 100 degrees C 960.8 degrees C 1950 degrees C 9. Carbon dioxide, CO2, is an example of a(n) a. b. c. d. Solution Compound Element Mixture 10. Which state of matter has a definite volume and a definite shape? a. b. c. d. Solid Liquid Gas plasma The engine of a model rocket accelerates the rocket vertically upward such that its speed is given by the following data. At t = 0, its speed is zero; at t = 1.00 s, its speed is 5.00 m/s; at t = 2.00 s, its speed is 10.0 m/s, at t = 3.00 s, its speed is 15.0 m/s, and at t = 4.00 s its speed is 20.0 m/s. Plot a velocity vs. time graph for this motion and from it determine the average acceleration. What do you expect its acceleration to be at t = 5.00 s? Why? What will its velocity be at t = 10.0 s if it continues at this acceleration? How far will it have traveled after 10 s?