Significant Figures, Conversions, Density Chemistry Name: _________________________ Date:_______________Period:______ Answer all questions, showing work as required. A. How many significant figures does each of the following numbers contain? 1. 5.432 g __________________________ 2. 2500.00 cm __________________________ 3. 3.58 x 10-9 nm __________________________ 4. 1.00 x 103 lb __________________________ 5. 0.00056 ML __________________________ B. Do the appropriate calculations for each of the following: 6. 12 cm + 0.031 cm + 7.969 cm __________________________ 7. 2.3 x 102 g + 4.62 x 102 g + 3.852 x 103g __________________________ 8. 0.0653 g + 0.08538 g + 0.07654 g + 0.0432 g __________________________ 9. 62.47 g – 39.9 g __________________________ 10. 40.081 mL – 29.094 mL __________________________ 11. 2.89 cm x 4.02 cm __________________________ 12. 9.13 x 10-4 cm x1.2 x 10-3 cm __________________________ 13. 109.3758 m2 / 5.813 m __________________________ 14. 6.023 x 1023 g / 8.513 x 1012 g __________________________ C. Do the following problems (remember D= m/v): 15. What is the density of a wood block that has a volume of 5.0 mL and a mass of 30.5 g? 16. What volume would a rock occupy if it had a mass of 31.2 g and a density of 10.4 g/mL? 17. Calculate the mass of a wooden block that is 4 cm x 2cm x 6 cm, and has a density of 0.5 g/cm3? (V = lxwxh) D. Solve the following conversions: 18. Two objects are separated by 60 miles. What is this distance in km? ( 1 mile = 1610 meters; 1 m = 1000m) 19. A student has a mass of 300 kg. How much does he weigh in pounds? (1 kg = 1000g ; 454 g = 1 pound) 20. Express the mass of a 1400 mg cockroach in ounces. ( 1000 milligram =1 g; 28.35 grams = 1 ounce) 21. The skyrocket you shot off on the Fourth of July traveled at a speed of 145.6 m/s. What is the rockets speed in km/hr? (1000 m = 1 km)