Periodic Elements with their Symbols and Atomic Numbers

Frequently Asked Questions

Why is the periodic table important?

The periodic table is important because it can be utilized to determine the properties of elements, even those that have not yet been found. Columns and rows demonstrate elements that share similar properties. Chemical equations are also balanced by the periodic table element properties are evident and straightforward by making trends via the periodic table.

How do you explain the periodic element?

The 118 known elements are arranged in a systematic order in the modern periodic table. These elements are organized in order of increasing atomic number, or the number of protons in an atom’s nucleus, which typically corresponds with increasing atomic mass, from left to right and top to bottom. The periodic table’s horizontal rows are known as periods, and each period number represents the number of orbitals that each element in that row has.

For example, elements in the first period have one atomic orbital where electrons spin; those in period 2 have two; those in period 3 have three; and so on and so forth until period 7. The atomic elements that have the same number of valence electrons, or electrons in the outermost orbital shell, are represented by the columns, or groups, on the periodic table.

What are the atomic number and atomic mass?

Atomic number

The atomic number is defined as the total number of protons in the nucleus of an atom that is the atomic number. It is symbolized by Z.

Mass number

The sum of neutrons and protons is equal to the mass number of an atom.

For example, the carbon atom has 6 protons and 6 neutrons so its mass number is 12 and its atomic number is 6. Always keep in mind number of protons same and the number of neutrons can change in the atoms of an element.

What is valency with example?

Valency is the measure of how many electrons an atom gains or loses to complete its outermost shell. By completing their outermost shell, or octet, the atoms become stable (8 electrons in the outmost shell).

Example:

Electronic configuration 2, and 6 is present in the oxygen. This means that it has 6 electrons in its outermost orbit or shell. In order to complete the octet, it will therefore require two extra electrons. So its valency is two.

How do you find valency?

• Eight electrons can fit inside a valence shell at most.
• As a result, a valence shell’s electron count might range from 1 to 8.
• Now imagine that an atom contains 1, 2, or 3 valence electrons.
• It is simpler for them to lose 1, 2, and 3 electrons from the valence to complete an octet, respectively.
• Valency of atom losing 1 electron = 1
• Valency of atom losing 2 electrons = 2
• Valency of an atom losing 3 electrons = 3

What is meant by oxidation state?

The total amount of electrons that a specific atom in a chemical reaction can accept, give, or share with any other atom is known as its oxidation state. The oxidation state not only represents anything numerically but also shows whether an atom is negatively or positively charged.

How do you find the oxidation state?

The following guidelines can be used to assign an oxidation state to a specific element or molecule.

• Any element that is in a free state has a zero oxidation number.
• For monoatomic ions, the oxidation number is always equal to the ion’s corresponding net charge.
• The oxidation state of the hydrogen atom (H) is 1. However, it displays an oxidation number of -1 when coupled with an element that has a lower electronegativity than it.
• Most of the substances that oxygen is found in have an oxidation of -2. But the oxidation number of oxygen in peroxide is -1.
• The oxidation state of all alkali metals (group 1 elements) in their compounds is one.
• An oxidation state is two present in all group 2 elements known as alkaline earth metals.
• Halogens (group 17 elements) are given an oxidation number of -1 in compounds composed of two elements.
• For neutral compounds, the total oxidation number of the atoms that make up the chemical is zero.
• When polyatomic ions, their net charge is equal to the total oxidation numbers of the atoms that make them up.