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Question 23

In the purification of town water supply, alum is used principally to:

  • A.kill bacteria.
  • B.control the pH of water.
  • C.improve the taste of the water.
  • D.coagulate small panicles of mud.
Objective

Question details

Exam body
NDA
Subject
Chemistry
Year
2011/2012
Question no.
#23
Type
Objective
Previous · Q22The atomic numbers of two elements X and Y are 12 and 9 respectively. The bond… Next · Q24 An increase in temperature causes an increase in the pressure and the _____

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