Table of Contents
What is Meant by Lanthanide Contraction?
Lanthanide contraction is the name given to the observed decrease in size of the atoms of the lanthanide series of elements, as one moves from left to right across the series. This is thought to be due to the filling of the 4f electron shell, which causes a decrease in the size of the atom.
About Lanthanide Contraction
The lanthanide contraction is a term used in chemistry to describe the trend in atomic radius as one moves from the first to the last lanthanide element in the periodic table. The trend is due to the increasing effective nuclear charge as one moves down the group. This effect is countered by the increasing number of protons in the nucleus, which causes the outermost electrons to be repelled more strongly.
Consequences of Lanthanide Contraction
When an atom absorbs a photon and gains energy, it can either lose that energy by emitting a photon or it can use that energy to cause the atom’s electron to move to a higher energy level. When an atom’s electron moves to a higher energy level, the atom shrinks in size. This is called Lanthanide contraction.
Lanthanide contraction occurs because the higher energy levels are closer to the nucleus than the lower energy levels. When an atom’s electron moves to a higher energy level, the atom’s nucleus pulls the electron in closer. This causes the atom to shrink in size.
The Lanthanide contraction is not a large effect, but it is measurable. The amount of contraction depends on the energy of the photon that was absorbed. The higher the energy of the photon, the more the atom will shrink.
The Lanthanide contraction is most noticeable in atoms that have a lot of electrons. Atoms that have a lot of electrons are called “dense” atoms. The Lanthanide contraction is most noticeable in dense atoms because they have more electrons to pull in close to the nucleus.
The Lanthanide contraction is not a danger to humans. It is not harmful and it does not cause any physical changes to the atom.
Case Study
A company is considering a new project that would require an investment of $10 million. The company expects the project to generate cash flows of $3 million per year for the next five years. The company’s required rate of return is 10%.
The NPV of the project is $1,944,444.
The company should accept the project because the NPV is positive.
Mercury – the Liquid Metal
Planet Mercury is the closest planet to the sun. It is also the smallest planet in the solar system. Mercury is a small, rocky planet. It is the only planet in the solar system that is not made mostly of gas.
Mercury is a hot, dry planet. The temperature on the surface can reach up to 800 degrees Fahrenheit (427 degrees Celsius). Mercury has no atmosphere. This means that there is no air to protect the planet from the sun’s heat.
The surface of Mercury is covered in craters. These craters were created when objects hit the planet’s surface. Mercury also has a number of volcanoes.
The planet Mercury was named after the Roman god Mercury. Mercury was the god of commerce, travel, and thieves.
Cause of Lanthanide Contraction
The cause of lanthanide contraction is not fully understood, but it is thought to be due to the electron configuration of the elements. Lanthanide contraction is most pronounced in the elements with the most stable electron configurations, such as cerium and lanthanum.
Shielding Effect on the Atomic Radii
The shielding effect on the atomic radii is the result of the electron shells that surround the nucleus. The first electron shell (K shell) has the least shielding effect, while the outermost electron shell (the eighth shell) has the most shielding effect. This is because the electrons in the outermost shell are the farthest from the nucleus and are less likely to be affected by the nuclear charge.
