The incorrect statement among the following that describes the propert...
Incorrect Statement about Lanthanides
Lanthanides are a group of metallic elements that belong to the f-block of the periodic table. They have similar properties and exhibit variable oxidation states. However, the incorrect statement among the following that describes the property of lanthanides is:
B) Lanthanide elements are all coloured.
Explanation
Lanthanides are known for their unique optical properties due to the presence of f-electrons. These elements exhibit a variety of colours due to electronic transitions between different energy levels. However, not all lanthanide elements are coloured. Some of them are colourless or have a white/silver appearance, such as lutetium and europium.
Correct Statements about Lanthanides
A) They exhibit variable oxidation states either 2 and 3 or 3 and 4.
Lanthanides have a tendency to lose two or three electrons to form cations with a +2 or +3 charge. However, some elements can also lose four electrons to form cations with a +4 charge, such as cerium and praseodymium.
C) The magnetic moment of Ln depends only on their unpaired electrons.
Lanthanides have unpaired electrons in their 4f orbitals, which make them magnetic. The magnetic moment of lanthanides depends on the number of unpaired electrons and their orientation in the crystal lattice.
D) The coordination number of aquated lanthanide ion is usually nine.
Lanthanide ions in aqueous solutions have a coordination number of nine due to the presence of water molecules as ligands. This coordination number can vary depending on the nature of the ligands and the oxidation state of the lanthanide ion.
Conclusion
Lanthanides are a unique group of metallic elements that exhibit a variety of chemical and physical properties. They have similar properties due to the presence of f-electrons and are used in various applications such as catalysts, magnets, and lighting.
The incorrect statement among the following that describes the propert...
Because all the lanthanides are not coloured ex-la3+ , lu3+, ce3+, etc