Question

Name the type of ion which causes hardness of water

Answer 1

Hard water contain dissolved in magnesium & calcium ions these make it more difficult for water to form a lather with soap Temporary hardness is caused by dissolved calcium Hydrocarbon which removed boiling....

Answer 2

Calcium carbonate hardness is a general term that shows the aggregate amount of divalent salts exhibit and does not particularly recognize whether calcium, magnesium or potentially some other divalent salt is causing water hardness.  

As should be obvious heating up the water causes the precipitation of strong calcium carbonate or strong magnesium carbonate. This expels the calcium particles or magnesium particles from the water, thus evacuates the hardness. In this way, hardness because of hydrogen carbonates is said to be impermanent.