Lawrencium

As we know, the periodic table is one of the most important parts of chemistry. It contains 118 elements which have different properties and characteristics. A periodic table is divided into four blocks named s-block, p-block, d-block and f-block. The d and f block elements show chemical properties transitionally between s and p block elements that’s why they are called transition and inner transition elements respectively. The inner transition elements or the f block elements are divided into lanthanides and actinides.

In this article, we are going to discuss the atomic number 103 which is lawrencium, its electronic configuration, ionic size, oxidation states, general characteristics and the comparison of actinides with lanthanide.

Actinides

Actinides are the elements of f block. They are commonly called actinide series. The actinides consist of total elements from Thorium to lawrencium. They all are radioactive in nature and have small half-lives which makes their study more difficult.

What is Atomic Number 103?

Lawrencium is the element with atomic number 103. It is a member of the actinides series. It is radioactive in nature like all other actinides with the smallest half-life of three minutes. Due to this fact it is prepared in only nanogram quantities which makes its study more difficult.

Electronic Configuration of Lawrencium

The electronic configuration of lawrencium is (Rn)5f¹⁴ 7s¹ 7p¹.

Ionic Size of Lawrencium

In actinide series, there is a gradual decrease in size of atoms or ions across the series. This decrease is termed as actinoid contraction. Thus, lawrencium has a low ionic size as compared to other members in the series.

Oxidation States of Lawrencium

The members of actinide series show a greater range of oxidation states as the 5f, 6d and 7s levels are of comparable energies. But unlike other members of the actinide series, lawrencium only shows +3 oxidation state which is a general oxidation state. The maximum oxidation state shown by actinides is +7.

General Characteristics of Lawrencium

The general characteristics of lawrencium are stated below:

• Like all other actinide metals, lawrencium is also silvery in appearance.

• It shows a variety of structures due to irregularities in metallic radii.

• It is highly reactive in nature.

• The magnetic properties of the actinides are very complex.

Comparison of Actinides with Lanthanide

On the basis of characteristic properties, actinides and lanthanides can be compared as follows:

• Actinides show greater structural variability than lanthanoids.

• They are highly reactive than lanthanoids.

• The magnetic properties of the actinides are more complex than lanthanoids.

• The ionization enthalpies of early actinides are lower than of the early lanthanoids.

Chemical Properties of Lawrencium

1. Group: Actinides

2. Period: 7

3. Block: f

4. Atomic Number: 103

5. State at room temperature (20oC): Solid

6. Electron configuration: (Rn) 5f¹⁴7s²7p¹

7. ChemSpider ID: 28934 (It is a free chemical structure database)

8. Melting point: 1627oC, 296oF, 1900 K

9. Relative atomic mass: 262

10. Oxidation states: +3

Properties of Lawrencium

1. Isotopes of this element are radioactive.

2. Isotopes of Lawrencium have a half-life of eleven hours.

3. It is not that much of use, mainly used in scientific research.

4. Lawrencium is of silver-white color.

5. In the actinide series, it is the heaviest element.

6. It is not available outside of the laboratory due to its short life.

7. For the position in the periodic table, its electron configuration is anomalous.

8. Lawrencium behaves as a heavier homolog to lutetium in the periodic table that chemistry experiments have confirmed.

9. Lawrencium is a trivalent element.

10. There are 13 isotopes of Lawrencium currently known, within them the most stable is 266 Lr, which has a half-life of 11 hrs, and the shorter-lived is 260 Lr which half-life is 2.7 minutes.

Application of Lawrencium

1. Due to its radioactive nature, Lawrencium does not have that much of use. Lawrencium is purely used for scientific research only.

2. There is no commercial use of Lawrencium as only a few atoms of this have been made.

3. This element can be used for technical purposes and harvesting energy.

4. The isotope of Lawrencium, 260 Lr is commonly used in chemistry, because it can be produced on a large scale.

5. Van der Waals radius of the Lawrencium atom is 246 pm.

Important Questions

1. State the electronic configuration and atomic number of lawrencium.

The electronic configuration of lawrencium is given as (Rn)5f¹⁴ 7s² 7p¹. Hence, the

the atomic number of lawrencium becomes 103.

2. What are the properties of lawrencium?

The various properties of lawrencium include the following:

• Silvery appearance.

• Variety of structures

• Highly reactive

• Complex magnetic properties.

3. Is lawrencium reactive?

Yes, lawrencium is reactive as it is a radioactive element.

Conclusion

Lawrencium is the element with atomic number 103. It is the member of the actinides series. It is radioactive in nature like all other actinides with the smallest half-life of three minutes. Due to this fact it is prepared in only nanogram quantities which makes its study more difficult. actinides show greater structural variability than lanthanoids. They are highly reactive than lanthanoids. The magnetic properties of the actinides are more complex than lanthanoids. The ionization enthalpies of early actinides are lower than of the early lanthanoids.