Home
Class 12
CHEMISTRY
Explain the following observations: (...

Explain the following observations:
(i) Generally, there is an increase in density of elements from titanium (Z = 22) to copper (Z = 29) in the first series of transition elements.
(ii) Transition elements and their compounds are generally found to be good catalysts in chemical rections.

Text Solution

Verified by Experts

(i) As the atomic radii decreases moving across from titanium to Cu, so its volume will decrease and density is expected to increase.
(ii) Good catalytic properties are due to following reasons:
Variable oxidation states due to which they can form a variety of unstable intermediate products.
Large surface area so that the reactants are adsorbed on the surface and come closer to each other facilitating the reaction process.
Promotional Banner

Topper's Solved these Questions

  • D - BLOCK ELEMENTS F - BLOCK ELEMENTS

    OSWAAL PUBLICATION|Exercise TOPIC-1 (D - BLOCK ELEMENTS, THEIR PROPERTIES AND COMPONDS) LONG ANSWER TYPE QUESTIONS - I|20 Videos

  • D - BLOCK ELEMENTS F - BLOCK ELEMENTS

    OSWAAL PUBLICATION|Exercise TOPIC-1 (D - BLOCK ELEMENTS, THEIR PROPERTIES AND COMPONDS)LONG ANSWER TYPE QUESTIONS - II|12 Videos

  • D - BLOCK ELEMENTS F - BLOCK ELEMENTS

    OSWAAL PUBLICATION|Exercise TOPIC - 2 (F - BLOCK ELEMENT , LANTHANOIDS AND ACTINOIDS)(LONG ANSWER TYPES QUESTIONS)|6 Videos

  • CO-ORDINATION COMPOUNDS

    OSWAAL PUBLICATION|Exercise TOPIC-2 (WERNER.S THEORY BONDING IN CO-ORDINATION COMPOUND , VBT, CFT AND IMPORTANCE OF CO-ORDINATION COMPOUNDS) (Very Answer Type Questions)|19 Videos

  • ELECTRO-CHEMISTRY

    OSWAAL PUBLICATION|Exercise Topic - 3 ELECTROLYSIS , LAWS OF ELECTROLYSIS, BATTERIES, FUEL CELLS AND CORROSION (LONG ANSWER TYPE QUESTIONS)|4 Videos

Similar Questions

Explore conceptually related problems

Give reasons: i) Generally there is increase in density along 3d series of transition metals.

Write the general electronic configuration of 3d series of transition elements.

Explain the following observations: (i) Transition elements generally form coloured compounds. (ii) Zinc is not regarded as transition element.

Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?

Assign reasons for each of the following: (i) Transition metals generally form coloured compounds. (ii) Manganese exhibits the highest oxidation state of +7 among the 3d-series of transition elements.

How would you account for the following: (i) Among lanthanoids, Ln (III) compounds are predominant. However, occasionally in solutions or in solid compounds, +2 and +4 ions are also obtained. (ii) The E_(M^(2+)//M)^(0) for copper is positive (0.34 V). Copper is the only metal in the first series of transition elements showing this behaviour. (iii) The metallic radii of the third (5d) series of transition metals are nearly the same as those of the corresponding members of the second series.

Explain giving reasons : (i) Transition metals and their compounds generally exhibit a paramagnetic behaviour. (ii) The chemistry of actinoids is not so smooth as that of lanthanoids.

(a) Give reasons for the following observations: (i) Cu^(+) ion is not stable in aqueous solution. (ii) Mn (II) ion shows maximum paramagnetic character amongst the bivalent ions of first transition series. (iii) Scandium (At. no. 21) salts are white. (b) Describe the reactions involved in the preparation of K_2Cr_2O_7 from chromite ore.

OSWAAL PUBLICATION-D - BLOCK ELEMENTS F - BLOCK ELEMENTS -TOPIC-1 (D - BLOCK ELEMENTS, THEIR PROPERTIES AND COMPONDS)(SHORT ANSWER TYPE QUESTIONS - I)
  1. Explain briefly how +2 state becomes more and more stable in the first...

    Text Solution

    |

  2. Name be oxo-metal anions of the first series of the transition metals ...

    Text Solution

    |

  3. What are the characteristics of the transition elements and why are th...

    Text Solution

    |

  4. In what way is the electronic configuration of transition elements dif...

    Text Solution

    |

  5. How is potassium permanganate ( KMnO4) prepared from MnO2 ? write the ...

    Text Solution

    |

  6. Write the structure of MnO4^(2-) and MnO(4)^(-) ions.

    Text Solution

    |

  7. Explain why: (i) E^0 for Mn^(3+)//Mn^(2+) couple is more positive th...

    Text Solution

    |

  8. Complete the following chemical equations: (i) MnO(4)^(-) (aq) + S2O...

    Text Solution

    |

  9. Assign reasons for the following: (i) Copper (I) ion is not known in...

    Text Solution

    |

  10. Assign reasons for each of the following: (i) Transition metals gene...

    Text Solution

    |

  11. How would you account for the following: (i) Cr^(2+) is reducing in ...

    Text Solution

    |

  12. State reasons for the following: (i) Cu(I) ion is not stable in an a...

    Text Solution

    |

  13. Explain giving reasons : (i) Transition metals and their compounds g...

    Text Solution

    |

  14. Account for the following: (i) Cu^(+) ions are not stable in aqueous s...

    Text Solution

    |

  15. How would you account for the following: (i) The atomic radii of the...

    Text Solution

    |

  16. Name the reaction that takes place when a mixture of potassium dichrom...

    Text Solution

    |

  17. Account for the following: (i) In the series Sc to Zn, the enthalpy ...

    Text Solution

    |

  18. Account for the following: (i) Transition elements exhibit higher en...

    Text Solution

    |

  19. Explain the following observations: (i) Generally, there is an incr...

    Text Solution

    |

  20. Explain the following observations: (i) Transition elements generall...

    Text Solution

    |