DENSITY, VISCOSITY, BUOYANCY TAKS QUESTIONS July 2004 – 11: (17) Swimmers find that they can float more easily in the ocean than in a freshwater pond. The most likely reason for this phenomenon is that the — A viscosity of pond water is greater than that of ocean water B* density of ocean water is higher than that of pond water C temperature of pond water is lower than that of ocean water D mass of ocean water is greater than that of pond water July 2004 – 11: (35) Compared to 250 g of gaseous nitrogen, 250 g of liquid nitrogen has greater — A volume B temperature C mass D* density Spring 2003 – 10: (31) What is the density at 20°C of 12.0 milliliters of a liquid that has a mass of 4.05 grams? A* 0.338 g/mL B 2.96 g/mL C 16.1 g/mL D 48.6 g/mL Spring 2003 – 11: 20 A sample of an element has a volume of 78.0 mL and a density of 1.85 g/mL. What is the mass in grams of the sample? Record and bubble in your answer to the nearest tenth on the answer document. Answer: 144.3 Spring 2003 – 11: 25 A block of maple wood with a volume of 405 cubic centimeters and a density of 0.67 g/cm3 is sawed in half. The density of the two smaller blocks is now — A one-fourth the original density B one-half the original density C two times the original density D* the same as the original density April 2004 – 10: (18) What is the mass of a 500.00 mL sample of seawater with a density of 1.025 g/mL? F 487.8 g G 500.0 g H* 512.5 g J 625.0 g April 2004 – 10: (27) Which of the following objects will float on water? Answer: D Spring 2004 - 11: (27) This pipette is filled with a 20% NaOH solution. The solution is at 20°C and has a density of 1.23 g/mL. According to this information, what is the mass of this NaOH solution? A 3.88 g B 15.7 g C* 23.9 g D 24.6 g October 2005 - 11: 18 A 500 mL quantity of vanilla ice cream has a mass of 400 grams. The manufacturer then bubbles air into the ice cream so that its volume increases by 300 mL. What is the ice cream’s approximate final density? F 0.30 g/cm 3 G* 0.50 g/cm 3 H 0.80 g/cm 3 J 1.30 g/cm 3 April 2004 – 10: 43 A bar of soap produced by this soap-making process normally sinks to the bottom of a container of water. Which of these processes could cause the bar of soap to float in water? A Making grooves in the surface of the thick paste B* Adding air bubbles to the thick paste C Letting the thick paste sit for four days D Chilling the mold filled with the thick paste July 2006 – 11, February 2006 - 11: 38 As the viscosity of a liquid increases, the liquid — F conducts electricity G* pours more slowly H evaporates more quickly J forms a precipitate July 2006 – 11: 43 Water normally boils at 100°C at sea level and at 97°C on a North American mountaintop. This difference in boiling points can be explained by the difference between the locations’— A ultraviolet light B* air pressure C gravitational force D thermal energy July 2006 – 11: 48 The buoyant force that a fluid exerts on objects is increased when there is an increase in the fluid’s — F acidity G clarity H solubility J* density Fall 2005 – 11: 19 Today, the observation that an air bubble in water rises to the surface is explained by the principle of — A. B. C. D. viscosity *buoyancy interference polarity Fall 2005 – 11: 25 Brown sugar consists of crystals of white sugar coated with molasses. If brown sugar hardens, it can be softened by heating. The most likely reason brown sugar softens when heated is that heat— A. increases the moisture of sugar B. decreases the volume of molasses C. increases the density of sugar D. *decreases the viscosity of molasses April 2006 – 11: 1 The picture shows the results of pouring a blue liquid into a clear liquid and allowing the mixture to settle for 25 minutes. Compared to the clear liquid, the blue liquid is more A massive B* dense C viscous D soluble April 2006 – 11: 23 The table shows properties of four liquids that are insoluble in water. If the four liquids are poured into an Erlenmeyer flask containing water, which liquid will form a layer below the water? A* Q BR CS DT April 2006 – 10: 22 Students in a chemistry lab measure the time it takes four different 100 mL solutions to pass through a hole in the bottom of a cup. Which of the following properties of the solutions is most likely being measured? F Buoyancy G Mass H* Viscosity J Volume April 2006 – 10: 29 A sample of water from a stream has a greater density than a sample of distilled water. Which is the best explanation for the difference in density? A Streams have kinetic energy. B Distilled water has a neutral pH. C* Streams can contain dissolved salts. D Distilled water can contain dissolved gases.