Name the members of the lanthanoid series which exhibit +4 oxidation state and those which exhibit +2 oxidation state. Try to correlate this type of behavior with the electronic configurations of these elements.
Name the members of the lanthanoid series which exhibit +4 oxidation state and those which exhibit +2 oxidation state. Try to correlate this type of behavior with the electronic configurations of these elements.
Solution and Explanation
The lanthanides that exhibit +2 and +4 states are shown in the given table. The atomic numbers of the elements are given in the parenthesis.
| +2 | +4 |
| Nd(60) | Ce(58) |
| Sm(62) | Pr(59) |
| Eu(63) | Nd(60) |
| Tm(69) | Tb(65) |
| Yb(70) | Dy(66) |
Ce after forming Ce4+ attains a stable electronic configuration of [Xe].
Tb after forming Tb4+ attains a stable electronic configuration of [Xe] 4f7.
Eu after forming Eu2+ attains a stable electronic configuration of [Xe] 4f7.
Yb after forming Yb2+ attains a stable electronic configuration of [Xe] 4f14.
Top Questions on d -and f -Block Elements
- Why is the ability of oxygen greater than fluorine to stabilise higher oxidation states of transition metals?
- CBSE CLASS XII - 2025
- Chemistry
- d -and f -Block Elements
- How do you prepare potassium manganate from pyrolusite ore?
- CBSE CLASS XII - 2025
- Chemistry
- d -and f -Block Elements
- Out of KMnO$_4$ and K$_2$MnO$_4$, which one is paramagnetic and why?
- CBSE CLASS XII - 2025
- Chemistry
- d -and f -Block Elements
- Assertion (A): First ionisation enthalpy of Cr is lower than that of Zn.
Reason (R): Zinc is a non-transition element.- CBSE CLASS XII - 2025
- Chemistry
- d -and f -Block Elements
- With increase in atomic number, the melting point of transition metals :
- CBSE CLASS XII - 2025
- Chemistry
- d -and f -Block Elements
Questions Asked in CBSE CLASS XII exam
- You are Reshmi of 17, Rose Valley, Avenue, Dehradun. You read the given advertisement and wish to apply for the post advertised. Write this job application along with your bio-data:
\includegraphics[width=0.75\linewidth]5.JPG
- CBSE CLASS XII - 2025
- Writing Skills
- ‘It is only war that makes people enemies.’ Analyse the theme of the lesson ‘The Enemy’ in the light of the above statement.
- CBSE CLASS XII - 2025
- Indian English Literature/Prose
- Your school has recently inaugurated a botanical garden in the school campus to educate children on the need to preserve species of plants and appreciate their significance in our lives. As a member of the student editorial board, write a report of the inaugural ceremony and details of the garden to be published in your school newsletter. You are Ayush of class XII A.
You may organize your report by following -
Who - What - When - Where - Why - Who- CBSE CLASS XII - 2025
- Report Writing
- You are Susheel of 10, R.K. Marg, New Delhi. You come across a report stating that a number of people in cities suffer from respiratory diseases, lung cancer, and heart diseases due to air pollution. Write a letter to the editor of a national daily expressing your concern and suggestions and ways to improve the situation.
\includegraphics[width=0.75\linewidth]5b.JPG- CBSE CLASS XII - 2025
- Letter Writing
- What do the images of nature signify in Keats’ A Thing of Beauty and Pablo Neruda’s Keeping Quiet?
CBSE CLASS XII Notification
GMC Azamgarh Admission 2025: Dates, Courses, Fees, Eligibility, SelectJuly 22, 2025Concepts Used:
Lanthanoids
Lanthanoids are at the top of these two-row, while actinoids are at the bottom row.
Properties of Lanthanoids
Lanthanoids are inclusive of 14 elements, with atomic numbers 58-71:
- Cerium - Xe 4f1 5d1 6s2
- Praseodymium - Xe 4f3 6s2
- Neodymium - Xe 4f4 6s2
- Promethium - Xe 4f5 6s2
- Samarium - Xe 4f6 6s2
- Europium - Xe 4f7 6s2
- Gadolinium - Xe 4f7 5d1 6s2
- Terbium - Xe 4f9 6s2
- Dysprosium - Xe 4f10 6s2
- Holmium - Xe 4f11 6s2
- Erbium - Xe 4f12 6s2
- Thulium - Xe 4f13 6s2
- Ytterbium - Xe 4f14 6s2
- Lutetium - Xe 4f14 5d1 6s2
These elements are also called rare earth elements. They are found naturally on the earth, and they're all radioactively stable except promethium, which is radioactive. A trend is one of the interesting properties of the lanthanoid elements, called lanthanide contraction.