11) volume: (3.14159) (2.00 cm)2 (27.75 cm) = 348.7165 cm3
mass: 188.870 g - 188.250 g = 0.620 g
density: 0.620 g / 0.3487165 L = 1.78 g/L
Note that cm3 became liters. Remember that gas density is measured in grams / liter. As a reminder: 1 cm3 = 1 mL and 1000 mL = 1 L.
12) volume of benzene: 15.55 g / (0.8786 g/cm3) = 17.6986 cm3
mass of silver: (10.50 g/cm3) (17.6986 cm3) = 185.8 g
13) volume of gold: 100.0 g ÷ (19.31 g/cm3) = 5.17866 cm3
mass of copper: (8.94 g/cm3) (5.17866 cm3) = 46.3 g
14) volume of aluminum: 100.0 g ÷ (2.70 g/cm3) = 37.037 cm3
mass of zinc: (7.14 g/cm3) (37.037 cm3) = 264 g
15) convert mm to cm: 8.50 mm x (1 cm/10 mm) = 0.850 cm
determine volume of sphere: (4/3) (3.14159) (0.850 cm)3 = 2.57 cm3
calculate density: 2.315 g / 2.57 cm3 = 0.900 g/cm3