Advertisements
Advertisements
Question
The second and third rows of transition elements resemble each other much more than they resemble the first row. Explain why?
Advertisements
Solution
Due to lanthanide contraction, the atomic radii of the second and third row transition elements are almost same. So, they resemble each other much more as compared to first row elements.
APPEARS IN
RELATED QUESTIONS
Complete the following chemical equations:
`(i) Cr_2O_7^(2-)+6Fe^(2+)+14H^+ ->`
`(ii) 2CrO_4^(2-)+2H^+ ->`
`(iii) 2MnO_4^-+5C_2O_4^(2-)+16H^+ ->`
Which is a stronger reducing agent, Cr2+ or Fe2+ and why?
Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?
How is the variability in oxidation states of transition metals different from that of the non-transition metals? Illustrate with examples.
What are inner transition elements?
Write the factors which are related to the colour of transition metal ions.
The paramagnetic character in the 3d-transition series elements increases up to Mn and then decreases.
Why do transition elements show variable oxidation states ? In 3d series (Sc to Zn), which elements shows the maximum number of oxidation state and why ?
Account for the following :
Ti4+ is colourless whereas V4+ is coloured in an aqueous solutions.
Transition metals with lowest melting point is ______.
In lake test for Al3+ ions, there is the formation of coloured ‘floating lake’. It is due to ______.
Metallic radii of some transition elements are given below. Which of these elements will have highest density?
| Element | \[\ce{Fe}\] | \[\ce{Co}\] | \[\ce{Ni}\] | \[\ce{Cu}\] |
| Metallic radii/pm | 126 | 125 | 125 | 128 |
Which of the following will not act as oxidising agents?
(i) \[\ce{CrO3}\]
(ii) \[\ce{MoO3}\]
(iii) \[\ce{WO3}\]
(iv) \[\ce{CrO^{2-}4}\]
Identify the metal and justify your answer.
\[\ce{MO3F}\]
The standard electrode potentials of four elements A, B, C and D are – 3.05, – 1.66, – 0.40 and + 0.80. The highest chemical reactivity will be exhibited by
Sodium this sulphate is used in photography because of its:-
Account for the following:
Transition metals form alloys.
Why Zn, Cd and Hg are not called transition metals?
Consider the following standard electrode potential values:
\[\ce{Fe^{3+}_{ (aq)} + e^- -> Fe^{2+}_{ (aq)}}\], E0 = +0.77 V
\[\ce{MnO^{-4}_{ (aq)} + 8H^+ + 5e^- -> Mn^{2+}_{ (aq)} + 4H2O_{(l)}}\], E0 = +1.51 V
What is the cell potential for the redox reaction?
Decide which of the following atomic numbers are the atomic numbers of the inner transition elements:
29, 59, 74, 95, 102, 104
