- Total Art Sulfuric Cued 1000g Amount Of Soy Pen 100g Of Surfer 98 Table 7 1 Major Constituents Of Seawater Lon 98x1 1 (75.65 KiB) Viewed 45 times
- Total Art Sulfuric Cued 1000g Amount Of Soy Pen 100g Of Surfer 98 Table 7 1 Major Constituents Of Seawater Lon 98x1 2 (64.99 KiB) Viewed 45 times
total Art Sulfuric cued = 1000g Amount of Soy Pen 100g of Surfer =98 Table 7.1. Major Constituents of Seawater lon =98x10000×10 Percent Chloride (CH) 55.04 Amount of SO4²-ing = 19.8× 1099 08504² Amount of Soy² = 98x10g of Sodium (Na) 30.61 Sulfate (SO) 7.68 Magnesium (Mg) 3.69 Calcium (Ca) 1.16 Potassium (K) 1.10 99.28 There are a number of ways to calculate the percentage of an ion in a solution. The numbers here are weight percents, or grams of each ion per 100 grams of salt. The remainder of the problem deals with two different cases. In Case #1 the H,SO, mixes into the uppermost 100 m of the water column and, as time passes, it spreads out laterally. Calculate the con- centration in seawater of SO, resulting from the spill when it has mixed into a volume of water 100 m (approximately 300 ft) on a side and 100 m thick. This calculation requires several steps, each of which is described below. Examining the effect of a tanker spill: During the summer of 1993 a tanker with a cargo of 10,000 tonnes (1 tonne is 1,000 kg or 10 grams) of sulfuric acid (H,SO) foundered off the Pacific coast of Mexico and began to leak the acid into the ocean. When sulfuric acid dissolves in water it dissociates to form positive lons (H) and negative ions (SO). b) First, calculate the volume (in cm) of the seawa- ter into which the H,SO, mixes. This volume is a rectangular solid 100 m on a side and 100 m thick Volume of Sea watu = 10¹ cm H is the ion that gives acids their acidic properties. Volume of Seawatu = 100x100x 1012cm3 106x106 cm³ Its fate in a mishap like this one is somewhat com- plex. We will consider the effect of the spill only on the SO, concentration of the surrounding seawater. Normal seawater (salinity-35%) contains 2.69 g SO, per kg of seawater. 35 g salt 1 kg water 7.68 g SO,*-* 100 g salt 2.69 g SO, 1 kg water X Problem 3: Imagine that the entire tanker cargo of H,SO, were to be spilled suddenly into the sur- rounding ocean. In this problem you will do some calculations to help you estimate the impact of that spill on the environment. These calculations are outlined in detail. They are to be done in the spaces provided, and the results are to be tabulated in the appropriate boxes of Table 7.2. c) Now calculate the mass (in kg) of the seawater in the volume you calculated above. Assume that the density of the water is 1.025 g/cm³. Remember that Mass (kg)-Volume (cm) x Density (- gm 1 kg -) x cm³ 10⁹ g Put your answer in the text block on the next page a.) First, calculate the total amount of SO,- (in grams) on board the tanker. (To do this, you need to determine how many grams of So, are in 10,000 tonnes of sulfuric acid. It is important to know that sulfuric acid consists 98 percent of SO, In other words, each gram of sulfuric acid contains 0.98 grams of SO). Express your results in scientific notation. *Note that this formula differs slightly from the one you were given in Problem 1. In problem 1 you were asked to calculate the mass in gm. In this problem you calculate mass in kg. This ac counts for the factor of 1/10 62 Exercise 7
clensity of wate=1g/cm²³ therefore mass of with=101²g Hey are mass of winter- точка MASSNia) 10¹² cm³y 1.0625) from the spil and the fraction that is naturall occur e.) Finally, determine the fraction of the SO,- in the contaminated volume of seawater that is derived ring ✓ 1035 = 10²2 cock 1.025 // 105 Tabela mesto Say ²= 2.6° - 1.025×10¹72gm d.) Next, calculate the concentration of SO, in the contaminated volume of seawater that is derived from the spill (in g SO,/kg seawater). Compare that concentration to the natural concentration of SO," in seawater. €12.498 %601 SOR27 from 41 Spill=c 12.49 %10 07 504² from Spill- 78.46 Concentration of Say Seill=9.86 of Seawater 8047kg Now repeat the above calculations (b. through e) for Case #2, in which the H,SO, has mixed into a volume of seawater 1 km on a side and 100 m thick. Again, do the calculations in the space provided and put the results in the appropriate column of Table 7.2. Table 7.2. Data sheet for Problem 3. Case #1 Case #2 1 Natural concentration of seawater SO,- ing SO/kg seawater (from discussion on page 62) 2.69 g SO, kg seawater 2.69 g SO kg seawater 2 Weight of spilled SO, in g (trom 3a) 9.8×10 9 89.8×10 7 8 Soy- S04- 3 Dimensions of volume of sea water length 100 m length 1 km width 100 m width 1 km depth 100 m depth 100 m 4 Seawater volume in cm (from 3b) 102 cm²³ 1014 cm³ 1.025X/09 1.025×10¹ kg Kg 5 Seawater weight in kg (from 3c) 6 Concentration of SO, derived from spilling SO/kg seawater (from 3d) 9.8 7 Fraction of So, in contaminated volume that is derived from the spill (from rows 1 and 6) 78.46 Chemical Aspects of Seawater 63