Home
Class 11
CHEMISTRY
The colour of K2Cr2O7changes from red-or...

The colour of `K_2Cr_2O_7`changes from red-orange to lemon yellow on treatment with aq.KOH because of:

A

Reduction of Cr(VI) to Cr(III)

B

Formation of chromium hydroxide

C

Conversion of dichromate into chromate ion

D

Oxidation of potassium hydroxide to potassium peroxide

Text Solution

Verified by Experts

The correct Answer is:
C
`underset("(red-orange)")(K_2Cr_2O_7 + 2KOH) to underset("(lemon- yellow)")(2K_2CrO_4 + H_2O)`
Promotional Banner

Topper's Solved these Questions

  • REDOX REACTIONS

    BRILLIANT PUBLICATION|Exercise LEVEL - II|50 Videos

  • REDOX REACTIONS

    BRILLIANT PUBLICATION|Exercise LEVEL - II (ASSERTION-REASON TYPE)|20 Videos

  • REDOX REACTIONS

    BRILLIANT PUBLICATION|Exercise LEVEL -III|50 Videos

  • PURIFICATION AND CHARACTERISATION OF ORGANIC COMPOUNDS

    BRILLIANT PUBLICATION|Exercise LEVEL- III (Linked Comprehension Tyne (Paragraph I))|12 Videos

  • S-BLOCK ELEMENTS

    BRILLIANT PUBLICATION|Exercise LEVEL-III (Linked Comprehension Type)|9 Videos

Similar Questions

Explore conceptually related problems

The colour of CoCl_(3).5NH_(3).H_(2)O is Orange yellow Orange Green Pink

Number of moles of K_2Cr_2O_7 , reduced by one mole of Sn^(2+) ions is:

In K_2 Cr_2 O_7 every Cr is linked to:

Assertion : In acidic medium, K_2 Cr_2 O_7 " exists as " Cr_2 O_7^(2-) (orange) while in basic medium it is converted to CrO_4^(2-) (yellow). Reason : K_2 Cr_2 O_7 is hygroscopic in nature and changes colour on reaction with water.

BRILLIANT PUBLICATION-REDOX REACTIONS-LEVEL - I
  1. The oxidation number of sulphur in S8, S2F2 and H2S are:

    Text Solution

    |

  2. In a reaction, 4 mole of electrons are transferred to 1 mole of HNO3, ...

    Text Solution

    |

  3. The colour of K2Cr2O7changes from red-orange to lemon yellow on treatm...

    Text Solution

    |

  4. One mole of hydrazine (N(2)H(4)) loses 10 moles of electrons in a reac...

    Text Solution

    |

  5. For the redox reaction, MnO4^(-) + C2O4^(2-) + H^(+) to Mn^(2+) + CO2 ...

    Text Solution

    |

  6. The oxidation state of chromium in the final product formed in the rea...

    Text Solution

    |

  7. Amongst the following, identify the species with an atom in +6 oxidati...

    Text Solution

    |

  8. The reaction of white phosphorous with aqueous NaOH gives phsophine al...

    Text Solution

    |

  9. Hydrogen peroxide in its reaction with KIO4 and NH2OH respectively, is...

    Text Solution

    |

  10. Arrange the following in the increasing order of oxidation state of Mn...

    Text Solution

    |

  11. Which of the following has least oxidation state of Fe?

    Text Solution

    |

  12. In the reaction, 8Al + 3Fe3O4 to 4Al2O3 + 9Fe, the number of electrons...

    Text Solution

    |

  13. In the balanced chemical reaction, IO3^(-) + aI^(-) + bH^(+) to cH2O +...

    Text Solution

    |

  14. In alkaline medium ClO2 oxidises H2O2 to O2 and itself gets reduced...

    Text Solution

    |

  15. The oxidation state of iodine in IPO4 is

    Text Solution

    |

  16. In alkaline medium, H2O2 reacts with Fe^(3+) and Mn^(2+) separately to...

    Text Solution

    |

  17. When hydrogen peroxide is added to acidified potassium dichromate, a b...

    Text Solution

    |

  18. Number of moles of MnO4^(-) required to oxidise one mole of ferrous ox...

    Text Solution

    |

  19. Freshly prepared, bright blue coloured solution of sodium in liquid am...

    Text Solution

    |

  20. The oxidation number of nitrogen atoms in NH4NO3 are

    Text Solution

    |