Home
Class 11
CHEMISTRY
CoS (black) obtained in group IV of salt...

`CoS` (black) obtained in group `IV` of salt analysis is dissolved in aqua regia and is treated with an excess of `NaHCO_(3)` and then `Br_(2)` water.An apple green coloured stable complex is formed. It is:

A

sodium cobaltocarbonate

B

sodium cobaltibromide

C

sodium cobalticarbonate

D

sodium cobaltobromide

Text Solution

Verified by Experts

The correct Answer is:
C
`CoCI_(2)+2naHCO_(3)rarr Co(HCO_(3))_(2)+2NaCI Co(HCO_(3))_(2)+4NaHCO_(3)`
`rarr Na_(4)[Co(CO_(3))_(3)]+3H_(2)O + 3CO_(2)`
`Br_(2)+H_(2)O rarr 2HBr +[O]`
`2Na_(4)[Co(CO_(3))_(3) +H_(2)O+[O]`
`rarr underset(("Sodium cobalticarbonate"))(2Na_(3)[CO(CO_(3))_(3)] ("Green") +2NaOH)`
Promotional Banner

Topper's Solved these Questions

  • SALT ANALYSIS

    GRB PUBLICATION|Exercise K: Vth and Vth Group Cations|10 Videos

  • SALT ANALYSIS

    GRB PUBLICATION|Exercise L: Miscellaneous|40 Videos

  • SALT ANALYSIS

    GRB PUBLICATION|Exercise I. IIIrd Group Cations|36 Videos

  • S BLOCK ELEMENTS

    GRB PUBLICATION|Exercise SUBJECTIVE TYPE|9 Videos

  • THERMODYNAMICS

    GRB PUBLICATION|Exercise All Questions|704 Videos

Similar Questions

Explore conceptually related problems

When one mole CrCl_3 .6H_2O is treated with excess of AgNo_3 , 3 mole of AgCl is obtained. The formula of complex is

A 5.0 g quantity of white phosphorus was burned in an excess of oxygen and the product was dissolved in water to make 250.0 mL solution. (a) Write balanced equations for the reaction. (b) When the solution was treated with an excess of aqueous Ca(NO_(3))_(2) , a white precipitate was obtained. What was it and how much it formed? (c ) The precipitate in part (b) was removed and the solution was treated with an excess of Zn , yielding a colourless gas collected at 20^(@)C and 742 mm of Hg . What was the gas and how much volume of it was formed?

GRB PUBLICATION-SALT ANALYSIS-J: IVth Group Cations
  1. An aqueous solution contains both Al^(3+) & Zn^(2+).To this solution N...

    Text Solution

    |

  2. A solution containing SCN^(-) ions can be used to test one or more out...

    Text Solution

    |

  3. The auxiliary reagent in group-IV reagent is:

    Text Solution

    |

  4. To avoid the precipitation of hydroxides of Ni^(2+),Co^(2+),Mn^(2+) al...

    Text Solution

    |

  5. A blue colouration (in solution or precipitate) is not obtained when:

    Text Solution

    |

  6. In the fourth group, white precipitate of Mn(OH)(2) on heating with Pb...

    Text Solution

    |

  7. A coloured solution of a salt gives following reactions: I. It gives...

    Text Solution

    |

  8. Zn(OH)(2)darr is soluble in:

    Text Solution

    |

  9. Which of the following metal sulphides has maximum solubility in water...

    Text Solution

    |

  10. A reddish pink substance on heating gives off a vapour which condenses...

    Text Solution

    |

  11. Among the following, buff colour metal sulphide is:

    Text Solution

    |

  12. Black colour compound A is insoluble in HCI solution but soluble in aq...

    Text Solution

    |

  13. When H(2)S gas a passed through an ammonical salt solution X, a slight...

    Text Solution

    |

  14. Buff coloured cyanide compound (A) reacts with excess of KCN in presen...

    Text Solution

    |

  15. Among the following, brownish black colour metal sulphide is:

    Text Solution

    |

  16. How many structural isomers can be possible for yellow complex?

    Text Solution

    |

  17. To increase significantly the concentration of free Zn^(2+) ion is a s...

    Text Solution

    |

  18. CoS (black) obtained in group IV of salt analysis is dissolved in aqua...

    Text Solution

    |

  19. A metal salt solution when treated with dimethyl glyoxime and NH(4)OH ...

    Text Solution

    |

  20. An aqueous solution of colourless metal sulphate M, gives a white prec...

    Text Solution

    |