Name: ________________________________________ Homework 3: Density and Temperature, properties of matter Note: pay special attention to sig figs in your answers!! 1. Perform the following conversions a. 5.5 feet into millimeters (2.54 cm = 1 in (exact), 12 in = 1 foot (exact)) b. 4.79 L into gallons (1 gal = 3.785 L) c. 75.4 days into seconds (time conversions are exact) d. 6.78 years into seconds (365 days in a year (not exact)) 2. Determine the volume (in mL) of 2.25 g of the following compounds. a) water, @20°C, d = 0.99823 g/1 mL b) Zinc, d = 7.10 g/1 mL 3. Using the temperature conversion that K = oC + 273.15 (not exact) convert the following a. 32oC into K b. 45.146oC into K c. 356.7 K into oC 4. Which of the following are chemical changes and which are physical changes? Briefly explain your choice!! (note – pages 59-63 in your text might be helpful!) a. a toaster filament becomes red hot ________________________________ b. the exposed flesh of the apple turns brown ________________________________ c. formation of snow from rain ________________________________ d. iron rusting ________________________________ e. fashioning a table leg from a piece of wood ________________________________