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Ok this is from my analytical chemistry class. Eventhough its not a MCAT problem the concepts involved are relevent to MCAT? I've tried this problem several times but I think I'm missing the Dimensional analysis part of this problem. Can anyone help me with this?
Thanks
Jason
Modern industrial society depends heavily on the availability and quality of water for industrial as well as drinking purposes. The water department of each municipality is responsible for monitoring the quality of the water, and conducts periodic analyses to see that the water meets certain minimum standards. One of the components of interest to industrial users is the amount of CaCO3 present in the water. When large amounts of calcium carbonate are present in boiler waters, the following reaction takes place when the water is heated,
This reaction causes calcium carbonate to deposit on the plumbing, thereby clogging the plumbing. This process is called scaling. EDTA is often added to boiler waters to complex the calcium and prevent the scaling. How many pounds of EDTA (372.25 g/mol) should be added to a 60,000 gallon boiler system to give a two-fold excess of EDTA over calcium (twice as many moles of EDTA as moles of Ca) if the hardness of the water is determined to be 118 ppm CaCO3 (100.09 g/mol)? [1 gallon is 3.78 liter; 1 ppm calcium carbonate is 1 mg calcium carbonate per liter; 454 grams per pound]
Thanks
Jason
Modern industrial society depends heavily on the availability and quality of water for industrial as well as drinking purposes. The water department of each municipality is responsible for monitoring the quality of the water, and conducts periodic analyses to see that the water meets certain minimum standards. One of the components of interest to industrial users is the amount of CaCO3 present in the water. When large amounts of calcium carbonate are present in boiler waters, the following reaction takes place when the water is heated,
Ca(HCO3)2
CaCO3 + H2O + CO2
This reaction causes calcium carbonate to deposit on the plumbing, thereby clogging the plumbing. This process is called scaling. EDTA is often added to boiler waters to complex the calcium and prevent the scaling. How many pounds of EDTA (372.25 g/mol) should be added to a 60,000 gallon boiler system to give a two-fold excess of EDTA over calcium (twice as many moles of EDTA as moles of Ca) if the hardness of the water is determined to be 118 ppm CaCO3 (100.09 g/mol)? [1 gallon is 3.78 liter; 1 ppm calcium carbonate is 1 mg calcium carbonate per liter; 454 grams per pound]