Classification of Elements & Periodicity in Properties Test 2

Fermium

• In bombardment experiments on plutonium, the radioactive element fermium was discovered in the U.S. in 1952.
• As with many of the other synthetic elements, it exists in amounts far too small to have practical uses outside the laboratory.
• In addition, the tiny amounts produced decay rapidly through intense radioactivity, giving them lifetimes measured in days, hours, or even microseconds.
• Fermium gets its name from Italian-American physicist Enrico Fermi who won the Nobel prize for Physics in 1938.

In an orbital, electrons are filled according to n+l rule.

This rule states that:

• Orbitals are filled in order of increasing (n + l), which represents the relative energy.
• If two orbitals have the same value of (n + l), they are filled in order of increasing n.

As for 2p and 3s, the n+l value is the same. But in the filling of electrons, 2p is filled first as its n value is less.

Ununoctium: The systematic element name for the chemical element with atomic number 118 (symbol Uuo). The element is now named oganesson.

For IUPAC nomenclature of elements with atomic number greater than 100, the abbreviation used for digit zero is n and name is nil.

The number of elements in each period is twice the number of atomic orbitals available in the energy level that is being filled.

Let's understand it by taking the elements of the 4th period.
In the fourth period, there are 18 elements. The types of subshells used in the 4th period are s, p, and d.
Number of orbitals of s subshell = 1
Number of orbitals of p subshell = 3
Number of orbitals of d subshell = 5
Total number of orbitals = 9
The total number of elements is 18 i.e. twice the total number of orbitals.

• Elements in the same group have the same number of valence electrons in their outermost shell, hence, have similar properties.
• Elements in the same period don't have same number of valence electrons, hence, have different properties. But, elements in the same period have same number of shells. 

The atomic number of sodium (Na) is 11. So its electronic configuration is 1s², 2s², 2p⁶, 3s¹.

Transition elements belong to d block and the first transition elements is scandium(whose atomic no. is 21)

Lanthanide series starts with the element Lanthanum(both names are similar).

The 4 orbitals filled in second period are one 2s (with 2 electrons) and three 2p (with 6 electrons).

Principle quantum no is defined as the no of shells an element possesses. Since every element in the 2nd period has 2 shells, therefore, principle quantum no for 2nd period is 2.

1st period contains only 2 elements hydrogen and helium having atomic no. 1 and 2 respectively.

The electronic configuration of hydrogen is 1s¹ while that of helium is 1s². Both contain only s subshell. S subshell that only contains 1 orbital i.e. z.

Thus, 1st period has 1 orbital.

The transuranium elements (also known as transuranic elements) are the chemical elements with atomic numbers greater than 92 (the atomic number of uranium). All of these elements are unstable and decay radioactively into other elements.

The last element in the actinoid series is lawrencium, Lr.

► Lawrencium: Atomic number is 103 and its electronic configuration is [Rn]5f¹⁴6d¹7s². The most common oxidation state displayed by it is +3; because after losing 3 electrons, it attains stable f¹⁴configuration.

The Latin word commonly used for the digit 9 is “enn”. It is abbreviated as “e”.

There are 5 orbitals in a d subshell and each orbital can accommodate 2 electrons. Hence the maximum number of electrons that can be filled in 3d subshell is 10.

The periodic table also has a special name for its vertical columns. Each column is called a group. The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons.

• The arrangement of electrons in different shells and sub-shells is known as the electronic configuration of a particular element.
• The electronic configuration diagram represents an element in its ground state or stable state. There are a set of rules to remember while distributing off electrons in different orbits.

• The element was to be called unununium (with the corresponding symbol of Uuu),a systematic element name as a placeholder, until the element was discovered (and the discovery then confirmed) and a permanent name was decided on.
• Although widely used in the chemical community on all levels, from chemistry classrooms to advanced textbooks, the recommendations were mostly ignored among scientists in the field, who called it element 111, with the symbol of E111, (111) or even simply 111.