Home
Class 12
CHEMISTRY
Describe how the following steps can be ...

Describe how the following steps can be carried out?
(a) Recovery of Gold from leached gold metal complex.
(b) Conversion of Zirconium iodide to pure Zirconium.
(c) Formation of slag in the extraction of copper.
(Write the chemical equations also for the reactions involved)

Text Solution

Verified by Experts

(a) Leached gold complex is treated with Zinc and gold is recovered by displacement method
`2Au[(CN)_(2)]^(-)(aq) + Zn(s) to 2Au(s) + [Zn(CN)_(4)]^(2-)(aq)`
(b) Zirconium iodide is decomposed on a tungsten filament, electrically heated to 2075 K. Pure Zr metal is deposited on the filament.
`ZrI_(4) to Zr + I_(2)`
(c) Silica is added to the ore and heated. It helps to slag off iron oxide as iron silicate
`FeO + SiO_(2) to FeSiO_(3) ("slag")`
Promotional Banner

Topper's Solved these Questions

  • XII BOARDS

    XII BOARD PREVIOUS YEAR PAPER ENGLISH|Exercise SET- I|34 Videos

  • XII BOARDS

    XII BOARD PREVIOUS YEAR PAPER ENGLISH|Exercise SET- II|10 Videos

  • XII BOARDS

    XII BOARD PREVIOUS YEAR PAPER ENGLISH|Exercise QUESTION PAPER (SECTION-B)|10 Videos

  • SAMPLE PAPER 2019

    XII BOARD PREVIOUS YEAR PAPER ENGLISH|Exercise SECTION: D|1 Videos

Similar Questions

Explore conceptually related problems

Describe the role of (i) NaCN in the extraction of gold from gold ore. (ii) SiO_(2) in the extraction of copper from copper matter. (iii) Iodine in the refining of zirconium. Write chemical equations for the involved reactions.

What happens when piece of (a) zinc metal is added to copper sulphate solution ? (b) aluminium metal is added to dilute hydrochloric acid ? (c) silver metal is added to copper sulphate solution ? Also write the balanced chemical equation if the reaction occurs.

(a) Write the steps involved in the extraction of pure metals in the middle of the activity series from their carbonate ores. (b) How is copper extracted from its sulphuric ore ?Explain the variour steps supported by chemical equations. Draw labelled diagram from the electrolytic refining of copper.

The following is an extract from 'Metals in the Service of Man, Alexander and Street/Pelican 1976. 'Alumina (aluminium oxide) has a very high melting point of over 2000^@ C so that it cannot readily be liquefied. However, conversion of alumina to aluminium and oxygen, by electrolysis, can occur when it is dissolved in some other substance : The aluminium oxide for the electrolytic extraction of aluminium is obtained by heating aluminium hydroxide. Write the equation for this reaction.

From the following flowsheet for the extraction of pure metal, answer the given questions. (ii) Step B (reduction) can be carried out ny using :

Minerals from which metals can be extracted economically and easily are called ores.The extraction of metals from theirs ores involves the following processes. (i)Concentration. (ii)Calcination | roasting | leaching . (iii)Reduction. It is carried out be one of the following methods. Which of the following reactions reactions does not occur in Bessemer converter in the extraction of copper from chalcopyrites ?

The following is an extract from 'Metals in the Service of Man, Alexander and Street/Pelican 1976. 'Alumina (aluminium oxide) has a very high melting point of over 2000^@ C so that it cannot readily be liquefied. However, conversion of alumina to aluminium and oxygen, by electrolysis, can occur when it is dissolved in some other substance : Write the equation for the reaction that occurs at the cathode during the extraction of aluminium by electrolysis.

Statement-1:Extraction of gold from its native ore involves leaching the metal ore with dilute solution of NaCN in presence of air. Statement-2:This is an oxidation reaction and leads to the formation of a soluble complex.

Explain the following (a) Although Au is soluble in aqua-regia, Ag is not (b) Zinc and hot copper is used for recovery of Ag from the complex [Ag(CN)_(2)]^(-) (c) Aluminium metal is frequently used as a reducing agent for extraction of metal such as chromium manganese etc. (d) Partial roasting of sulphide ore is done in the metallurgy of copper.

Write the balanced chemical equations for the following reaction. (a) Sodium carbonate on reaction with hydrochloric acid in equal molar concentrations gives sodium chloride and sodium hydrogen carbonate. (b) Sodium hydrogen carbonate on reaction with hydrochloric acid gives sodium chloride, water and liberates carbon dioxide. (c) Copper sulphate on treatment with potassium iodide precipitates cuprous iodide iodide (Cu_(2)I_(2)) , liberates iodine gas and also forms potassium sulphate.

XII BOARD PREVIOUS YEAR PAPER ENGLISH-XII BOARDS-QUESTION PAPER (SECTION-C)
  1. Give reasons for the following : (a) When 2g of benzoic acid is diss...

    Text Solution

    |

  2. An alcohol [A] with molecules formula (C(4)H(10)O) o oxidation with ac...

    Text Solution

    |

  3. Which one of the following compounds will undergo hydrolysis at a fast...

    Text Solution

    |

  4. A compound is formed by the substitution of two chlorine atoms for two...

    Text Solution

    |

  5. Give reasons for the following : (i) Use of aspartame as an artifici...

    Text Solution

    |

  6. (a) Name the branched chain component of starch. (b) Ribose in RNA a...

    Text Solution

    |

  7. Give three reactions of glucose which cannot be explained by its open ...

    Text Solution

    |

  8. The following data were obtained during the first order thermal decomp...

    Text Solution

    |

  9. Two reactions of the same order have equal pre exponential factors but...

    Text Solution

    |

  10. (a) A colloidal sol is prepared by the given method in figure. What is...

    Text Solution

    |

  11. Describe how the following steps can be carried out? (a) Recovery o...

    Text Solution

    |

  12. Explain the use of the following : (a) NaCN in Froth Floatation Method...

    Text Solution

    |

  13. Explain the following : (a) Out of Sc^(3+), Co^(2+) " and "Cr^(3+) "...

    Text Solution

    |

  14. A metal complex having composition Cr(NH(3))(4)CI(2)Br has been isolat...

    Text Solution

    |

  15. (a) Identify A-D (b) Distinguish between the following pair of compo...

    Text Solution

    |

  16. (a) Account for the following : (i) Direct nitration of aniline yie...

    Text Solution

    |

  17. (a) A cell is prepared by dipping a zinc rod in 1M zinc sulphate solut...

    Text Solution

    |

  18. (a) Apply Kohlrausch law of independent migration of ions, write the e...

    Text Solution

    |

  19. (a) Account for the following observations : (i) SF(4) is easily hyd...

    Text Solution

    |

  20. (a) What inspired N.Bartlett for carrying out reaction between Xe and ...

    Text Solution

    |