|1 Crore+ students have signed up on EduRev. Have you?|
Due to lanthanide contraction:
Which of the following statements concerning lanthanides elements is false:
Which of the following statements is not correct:
The lanthanide contraction is responsible for the fact that:
The electronic configuration of (Gd) (At. No. 64) is:
Which one of the following elements shows maximum number of different oxidation states in its compounds:
Cerium (Z = 58) is an important member of lanthanides. Which of the following statements about cerium is incorrect:
Which of the following factors may be regarded as the main cause of lanthanide contraction:
Ln3+ (trivalent lanthanides ions) have electronic configurations:
The common oxidation state of the elements of lanthanide series is:
Lanthanide for which +II and +III oxidation states are common is:
The separation of lanthanides in ion exchange method is based on:
Which of the following forms stable + 4 oxidation state:
The common oxidation state of Cerium are +3 and +4.
Zr and Hf have similar atomic and ionic radii because:
In general, the configuration of lanthanides is (n – 2) f1-14 (n – 1) s2 p6 d1or 0 ns2. It is observed that, with increase in atomic number of lanthanides, there is a decrease of ionic radii from La : 122 to Lu : 0.99 (Å).
The properties of zirconium and hafnium atoms and ions are almost the same because both:
The atomic radius of the metal zirconium, Zr, (a period-5 transition element) is 159 pm and that of hafnium, Hf, (the corresponding period-6 element) is 156 pm. The ionic radius of Zr4+ is 79 pm and that of Hf4+ is 78 pm. The radii are very similar even though the number of electrons increases from 40 to 72 and the atomic mass increases from 91.22 to 178.49 g/mol.
This is due to Lanthanide contraction i.e. greater-than-expected decrease in ionic radii of the elements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, which results in smaller than otherwise expected ionic radii
What would be magnetic moment of Gd+3 (Z=64)?
Correct option is B)
Electronic configuration of [Gd]3+:[Xe]4f7
Hence number of unpaired electron n=7
Hence, magnetic moment=n(n+2)=63=7.9BM