Advertisements
Advertisements
प्रश्न
Name the radioactive element in lanthanoids.
उत्तर
Promethium (Pm)
APPEARS IN
संबंधित प्रश्न
Give the electronic configuration of europium (Z = 63).
Explain the trend in an Oxidation state of 3d elements.
Which of the following statements are FALSE about lanthanoids?
(I) They have lower heat of atomization than transition metals
(II) They are soft metals with silvery white colour and densities of about 7 g cm−3.
(III) They react with water to give the metal hydroxide and oxygen gas.
(IV) They form hydroxides, which are covalent and basic.
The electronic configuration of transition element 'X' in +3 oxidation state is [Ar] 3d4. What is its atomic number?
Which statement(s) is/are CORRECT about applications of lanthanoid metals/ions and their compounds?
(I) The optoelectronics applications use lanthanoid ions as active ions in luminescent materials.
(II) Lanthanoid compounds are used in television tubes.
(III) Lanthanoids are used in hybrid cars, superconductors and permanent magnets.
The only radioactive element among the lanthanoids is ____________.
When lanthanoids (Ln) are heated to about 2800 K with carbon, the carbides with general formula ____________ are obtained.
What is the general molecular formula of the product obtained on reacting lanthanoids (Ln) with nitrogen?
The observed electronic configuration of promethium (atomic number 61) is ____________.
Which element from following forms colourless compounds in +2 oxidation state?
Identify the correct decreasing order of ionic radii of lanthanoids.
Which of the following properties is NOT of lanthanoids?
Identify the formula of lanthanoid oxide formed when lanthanoid (Ln) is burnt in oxygen.
Which among the following lanthanoids has smallest atomic size?
Which of the following factors may be regarded as the main cause of lanthanoid contraction?
The most basic hydroxide from the following is:
Identify the last element in lanthanoid series.
Which element from following has largest atomic radius?
Give the electronic configuration of gadolinium (Z = 64).
Write two uses of lanthanoids.
