The reaction of soda ash (Na2CO3) with calcium sulfate in water is represented by the following chemical reaction: Na2CO3 + CaSO4 >>> CaCO3 + Na2SO4. Assuming that this reaction is complete and that there is 153 mg/l of CaSO4 initially present, what is the mass of soda ash that must be added to 1 liter of the water? How many grams of CaO are required to be the chemical equivalent of 246 g of Mg(HCO3)2?
A complete reaction requires the number of CaSO4 to be equal to the number of moles of
Soda Ash.
Number of moles of CaSO4
1 liter has 153 mg of CaSO4, 1 mol of CaSO4 = 142.04g
Number of moles of CaSO4 = [(153 x 10-3) g x 1
142.04
]
=1.08 × 10-3mol
Number of moles of Soda Ash =1.08 × 10-3mol
1 mol of Soda Ash = 106g
Grams of Soda Ash = [(1.08 …show more content…
Nevertheless, there are a number of health effects that can arise from the intake of hard water. The presence of calcium, iron, magnesium and zinc reduce the rate of absorption these minerals in the small intestine. In addition, high amount of magnesium in the water can cause hypomagnesaemia where its excretion is limited. Laxative effect can also arise when both magnesium and sulfate are present. Diarrhea is a common effect of increased intake of magnesium salts.
The use of hard water as coolant in industries poses great financial implication on the operation of the industry. Hard water increase the maintenance cost on the machinery as a result of corrosion of the machine parts and as a result of the residues that are deposited on the machine. And ultimately it will affect the quality of the end product (Peavy, Rowe,
& Tchobanoglous, McGraw-Hill, Inc).
6. An analysis for BOD5 is to be run on a sample of wastewater. The BOD is expected to range from 50 350, and the dilutions are prepare accordingly. In each case, a standard BOD bottle is used. The data are recorded below. Determine the BOD5 of the wastewater.
Bottle Number Wastewater, mL
DOI
DO5
1
A complete reaction requires the number of CaSO4 to be equal to the number of moles of
Soda Ash.
Number of moles of CaSO4
1 liter has 153 mg of CaSO4, 1 mol of CaSO4 = 142.04g
Number of moles of CaSO4 = [(153 x 10-3) g x 1
142.04
]
=1.08 × 10-3mol
Number of moles of Soda Ash =1.08 × 10-3mol
1 mol of Soda Ash = 106g
Grams of Soda Ash = [(1.08 …show more content…
Nevertheless, there are a number of health effects that can arise from the intake of hard water. The presence of calcium, iron, magnesium and zinc reduce the rate of absorption these minerals in the small intestine. In addition, high amount of magnesium in the water can cause hypomagnesaemia where its excretion is limited. Laxative effect can also arise when both magnesium and sulfate are present. Diarrhea is a common effect of increased intake of magnesium salts.
The use of hard water as coolant in industries poses great financial implication on the operation of the industry. Hard water increase the maintenance cost on the machinery as a result of corrosion of the machine parts and as a result of the residues that are deposited on the machine. And ultimately it will affect the quality of the end product (Peavy, Rowe,
& Tchobanoglous, McGraw-Hill, Inc).
6. An analysis for BOD5 is to be run on a sample of wastewater. The BOD is expected to range from 50 350, and the dilutions are prepare accordingly. In each case, a standard BOD bottle is used. The data are recorded below. Determine the BOD5 of the wastewater.
Bottle Number Wastewater, mL
DOI
DO5
1