# properties, conversions, density

```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&deg;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 ________________________________
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