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Question 15

Hardness of water is usually due to the presence of

  • A.calcium hydroxide or magnesium hydroxide
  • B.calcium trioxocarbonate (IV)) or calcium tetraoxosulphate (VI)
  • C.sodium hydroxide or magnesium hydroxide
  • D.calcium chloride or sodium chloride salts
Objective

Question details

Exam body
UNN
Subject
Chemistry
Year
2017/2018 DAY 2
Question no.
#15
Type
Objective
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