Chemistry question?

0 ⤊

Water "softeners" remove metal ions such as Fe2+, Fe3+, Ca2+, and Mg2+ (which make water "hard") by replacing them with enough Na+ ions to maintain the same number of positive charges in the solution. If 6.5 103 L hard water is 0.015 M Ca2+ and 0.0010 M Fe3+, how many moles of Na+ are needed to replace these ions?

2007-09-27 02:34:42 · 1 answers · asked by ronnie c 1 in Science & Mathematics ➔ Chemistry

1 answers

6.5LH2O x 0.015molCa2+/1LH2O x 2molNa+/1molCa2+ = 0.195 moles Na+

6.5LH2O x 0.0010molFe3+/1LH2O x 3molNa+/1molFe3+ = 0.0195 moles Na+

0.0195 + 0.195 = 0.21 moles total Na+ (using two significant figures)

2007-09-27 02:46:00 · answer #1 · answered by steve_geo1 7 · 0⤊ 1⤋