Question

Answer the question based on the information provided. Use significant figures

In 1989 the Exxon Valdez ran aground and spilled 240,000 barrels of crude oil off the coast of Alaska, leaving an average 0.5 mm thick layer of oil covering the waters of Prince William Sound. Using the conversion factors given below, determine the area of the oil slick in square miles. 1 barrel = 42 gallons 1 US gallon = 3.7854 liters

Answer 1

Total amount of crude oil spilled = 240,000 barrels

                                                                = 240,000 x 42 gallons

                                                                = 240,000 x 42 x 3.7854 litres

                                                                = 38,156,832 litres

Thickness of oil spill layer = 0.5 mm

                                                   = 0.05 cm         (1 cm = 10 mm)

Thickness of oil layer x Total spillage area = Total volume of oil spill                          

Þ 0.05 cm x area (in square cm) = 38,156,832 liters

Þ 0.05 cm x area (in square cm) = 38,156,832 x 1000 cm³                             Note: (I L = 1000 cm³)

Þ Area (in square cm) = (38,156,832,000 cm³ )/ (0.05 cm) = 763,136,640,000 cm²

Since, 1 cm² = ‪0.00000000003861 square miles = 3.861 x 10^-11 miles

\ 763,136,640,000 cm² = 763,136,640,000 x ‪0.00000000003861 square miles

                                                = 29.4647 square miles

Thus, the area of oil slick = 29.4647 square miles