Class 12 Exam > Class 12 Questions > Knowing that the Chemistry of lanthanoids (Ln...
Start Learning for Free
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?
[AIEEE-09]
- a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.
- b)Ln (III) compounds are generally colourless.
- c)Ln (III) hydroxides are mainly basic in character.
- d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.
Correct answer is option 'B'. Can you explain this answer?
| FREE This question is part of | Download PDF Attempt this Test |
Most Upvoted Answer
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 ...
The incorrect statement is option B: Ln (III) compounds are generally colourless.
Explanation:
1. Ionic sizes of Ln (III) decrease with increasing atomic number:
The lanthanoids, also known as the lanthanide series, are a group of 15 elements that follow lanthanum in the periodic table. As we move across the series from lanthanum to lutetium, the atomic number increases, but the size of the ions decreases. This is due to the increase in effective nuclear charge, which attracts electrons more strongly and reduces the size of the ions. Therefore, the ionic sizes of Ln (III) generally decrease with increasing atomic number.
2. Ln (III) compounds being generally colourless:
Ln (III) compounds, in general, exhibit a wide range of colors due to the presence of partially filled 4f orbitals. The 4f electrons are shielded by 5s and 5p orbitals, resulting in less effective shielding and increased energy differences between the orbitals. This leads to absorption of specific wavelengths of light, resulting in the color observed for the compounds. Therefore, the statement that Ln (III) compounds are generally colorless is incorrect.
3. Ln (III) hydroxides are mainly basic in character:
Ln (III) hydroxides are basic in character. The Ln (III) ions have a high charge density, which results in strong electrostatic attraction between the ions and hydroxide ions. This leads to the formation of basic hydroxides. Therefore, the statement that Ln (III) hydroxides are mainly basic in character is correct.
4. Bonding in Ln (III) compounds is predominantly ionic in character:
The bonding in Ln (III) compounds is predominantly ionic in character. The Ln (III) ions have a high charge density and tend to lose their 3 valence electrons to achieve a stable noble gas configuration. This results in the formation of Ln (III) ions with a +3 charge, which can form ionic bonds with negatively charged ions. Therefore, the statement that the bonding in Ln (III) compounds is predominantly ionic in character is correct.
In conclusion, the incorrect statement is option B: Ln (III) compounds are generally colourless. Ln (III) compounds exhibit a wide range of colors due to the presence of partially filled 4f orbitals.
Explanation:
1. Ionic sizes of Ln (III) decrease with increasing atomic number:
The lanthanoids, also known as the lanthanide series, are a group of 15 elements that follow lanthanum in the periodic table. As we move across the series from lanthanum to lutetium, the atomic number increases, but the size of the ions decreases. This is due to the increase in effective nuclear charge, which attracts electrons more strongly and reduces the size of the ions. Therefore, the ionic sizes of Ln (III) generally decrease with increasing atomic number.
2. Ln (III) compounds being generally colourless:
Ln (III) compounds, in general, exhibit a wide range of colors due to the presence of partially filled 4f orbitals. The 4f electrons are shielded by 5s and 5p orbitals, resulting in less effective shielding and increased energy differences between the orbitals. This leads to absorption of specific wavelengths of light, resulting in the color observed for the compounds. Therefore, the statement that Ln (III) compounds are generally colorless is incorrect.
3. Ln (III) hydroxides are mainly basic in character:
Ln (III) hydroxides are basic in character. The Ln (III) ions have a high charge density, which results in strong electrostatic attraction between the ions and hydroxide ions. This leads to the formation of basic hydroxides. Therefore, the statement that Ln (III) hydroxides are mainly basic in character is correct.
4. Bonding in Ln (III) compounds is predominantly ionic in character:
The bonding in Ln (III) compounds is predominantly ionic in character. The Ln (III) ions have a high charge density and tend to lose their 3 valence electrons to achieve a stable noble gas configuration. This results in the formation of Ln (III) ions with a +3 charge, which can form ionic bonds with negatively charged ions. Therefore, the statement that the bonding in Ln (III) compounds is predominantly ionic in character is correct.
In conclusion, the incorrect statement is option B: Ln (III) compounds are generally colourless. Ln (III) compounds exhibit a wide range of colors due to the presence of partially filled 4f orbitals.
Free Test
FREE
| Start Free Test |
Community Answer
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 ...
The correct answer is option B
Ln(III) compounds are coloured due to the f−f transitions in the lanthanide but the colour is fainter as compared to the d−d transitions in transition metals.
Ln(III) compounds are coloured due to the f−f transitions in the lanthanide but the colour is fainter as compared to the d−d transitions in transition metals.
|
Explore Courses for Class 12 exam
|
|
Similar Class 12 Doubts
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer?
Question Description
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer?.
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer?.
Solutions for Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 12.
Download more important topics, notes, lectures and mock test series for Class 12 Exam by signing up for free.
Here you can find the meaning of Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer?, a detailed solution for Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Knowing that the Chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?[AIEEE-09]a)The ionic sizes of Ln (III) decrease in general with increasing atomic number.b)Ln (III) compounds are generally colourless.c)Ln (III) hydroxides are mainly basic in character.d)Because of the large size of the Ln (III)ions the bonding in its compounds is predominantly ionic in character.Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice Class 12 tests.
|
|
Explore Courses for Class 12 exam
|
|
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup