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Question 18

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
2017/2018
Question no.
#18
Type
Objective
Previous · Q17In an electrolytic cell, electrons enter the system through the Next · Q19 How many moles of alanine C 3 H 7 NO 2 , are there in 159g of alanine?

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