Which water softener "ties up" calcium ions and keeps them in solution?

Question

Quizplus · Accepted Answer

Zeolites are a type of resin commonly used in water softeners that can exchange sodium ions for calcium ions, effectively "tying up" the calcium and keeping it in solution. Sodium carbonate and sodium phosphate also have some ability to tie up calcium ions, but they are not typically used as water softening agents. Fatty acids are not used for water softening.

Which Water Softener "Ties Up" Calcium Ions and Keeps Them