Question

Which of the following groups of ions makes the
water hard ?
(a) Sodium and bicarbonate
(b) Magnesium and chloride
(c) Potassium and sulphate
(d) Ammonium and chloride

Answer 1

Answer:

magnesium and chloride

as calcium and magnesium ions make water hard

hope it helps u...

mark as brainliest

Answer 2

Answer:

(c) Magnesium Chloride makes the water hard. Substances such as washing Soda are used to remove the permanent hardness of water