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Question 0

Cr2O7 + 6Fe2+ + 14H+ → 2Cr3+ +6Fe3+ + 7H2O. In the above , the oxidation number of chromium changed from?

  • A.+7 to +3
  • B.+6 to +3
  • C.+5 to +3
  • D.-2 to +3
  • E.
Objective

Question details

Exam body
JAMB
Subject
Chemistry
Year
1990
Question no.
#0
Type
Objective
Previous · Q0In a reaction: SnO + 2C → Sn + 2CO, the mass of coke containing 80% carbon… Next · Q0 In the reaction 1O - 3 + 5l - + 6H + → 31 2 + 3H 2 O, the oxidizing agent is?

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