Which of the ions is colourless inspite of the presence of unpaired electrons ?A. `La^(3+)`B. `Eu^(3+)`C. `Gd^(3+)`D. `Lu^(3+)`

Which of the ions is colourless inspite of the presence of unpaired el

1.	Which of the ions is colourless inspite of the presence of unpaired electrons ?A. `La^(3+)`B. `Eu^(3+)`C. `Gd^(3+)`D. `Lu^(3+)`
Answer» Correct Answer - C Gadolinium does not absorb light in the visible region of the spectrum , hence it is colourless inspite of the presence of 7 unpaired electrons . Being colourless , gadolium is sometimes used as a support for other rate earth phosphors and luminesce in the knowledge that it will not quench their intense colour.

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Which of the ions is colourless inspite of the presence of unpaired electrons ?A. `La^(3+)`B. `Eu^(3+)`C. `Gd^(3+)`D. `Lu^(3+)`

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