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Question 15

Permanent hardness of water is due to the presence of calcium sulphate which is not softened by boiling. Which of the following chemical is normally used to soften it?

  • A.KMnO4
  • B.CaCl2
  • C.Na2CO3
  • D.FeSO4
Objective

Question details

Exam body
NDA
Subject
Chemistry
Year
2011/2012
Question no.
#15
Type
Objective
Previous · Q14Select the equation representing, the action of steam on red hot iron. Next · Q16 A suitable indicator used for titration of oxalic acid and sodium hydroxide is.

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