Awater treatment plant receives the source water with an average ca2+ concentration of 46.9 mg/l and mg2+ concentration of 14.8 mg/l. the plant is treating 80 million gallons of water per day. what mass of solids will be produced per day if all of the calcium and magnesium are converted to caco3(s) and mg(oh)2(s) in the softening process? give your answer in kg.

42,650 kg of calcium carbonate will be produced everyday.

13,600.5 kg of magnesium hydroxide will be produced everyday.

Explanation:

Concentration of calcium ions = 46.9 mg/L

Concentration of magnesium ions = 14.8  mg/L

Volume of solution treated everyday , V= 80 million gal

=

1 gallon = 4.546 Liter

Mass of  calcium ion in V =

=  

1 mg = 0.001 g

Moles of calcium ions =

From 1 mole of calcium ion 1mol of carbonate is formed . then from 426,500 moles of calcium ion will form :

of calcium carbonate

Mass of 426,500 moles of calcium carbonate:

426,500 mol × 100 g/mol  = 42,650,000 g = 42,650 kg

Mass of  magnesium ion in V =

=

=  

Moles of magnesium ions =

From 1 mole of magnesium ion 1 mol of magnesium hydroxide is formed . then from 224,250 moles of magnesium ion will form :

of magnesium hydroxide

Mass of 224,250 moles of magnesium hydroxide:

224,250 mol × 58 g/mol  = 13,006,500 g = 13,006.5 kg

42,650 kg of calcium carbonate will be produced everyday.

13,600.5 kg of magnesium hydroxide will be produced everyday.

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."