Hydrogen, a chemical element with the symbol H and atomic number1, is the lightest element in the periodic table with a standard atomic weightof 1.008. it is one of the most abundant chemical elements found in the universe. About75% of all baryonic mass are roughly constituting hydrogen.
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Hydrogen atom readily forms a covalent bond, it is mostly foundin a molecular form on the earth in the form of H2O or most organic compounds.No doubts hydrogen is the most widely used chemical species in the world ofchemistry and it is uses literally everywhere in chemistry.
You are here to know valence electrons and the valency of the hydrogen atom, aren’t you? But for this, you have to know what these two termsare, so without wasting your time let’s begin,
Difference Between Valence Electrons and Valency
Valence electrons are the total number of electrons presentin the outermost shell of an atom (i.e. in outermost orbital). The valenceelectrons for a neutral atom is always definite, it cannot be varied (more orless) in any condition for a particular atom and may or may not be equal to itsvalency.
Valency is defined as the total number of electrons an atomcan lose, gain, or share at the time of bond formation to get a stableelectronic configuration i.e. to complete an octet. The valency of an atom canbe variable in different compounds or chemical reactions due to the differentbonding circumstances. Most of the time valency varies/changes due to change inoxidation and reduction states.
Hydrogen (H) Valence Electrons
There are four simple steps to find out the valenceelectrons for hydrogen atom which are:
Step 1: Find the Atomic Number
To find out the atomic number of hydrogen, we can use theperiodic table. With the help of the periodic table, we can easily see that theatomic number of hydrogen is 1. As its atomic number is 1, it has one proton,and for neutral hydrogen, the number of protons is always equal to the number ofelectrons i.e. has only one electron in its nucleus.
Step 2: Write Electron Configuration
Electron configuration is the arrangement of electrons onthe orbitals. The hydrogen atom has only one electron on its shell, we have toput only one electron in its orbital and that will go in the 1s orbital as the Sorbital can hold a maximum of two electrons, and is closer to the nucleus.
Hydrogen electron configuration H (H) = 1s1 (completeconfiguration).
Step3: Determine Valence Shell
As we know, the valence shell of an atom can be found fromthe highest number of principle quantum numbers which is expressed in the termof n, and in 1s1, the highest value of n is 1 so that the valence shell of H is1s1.
Step 4: Find Valence Electrons
The total number of electrons present in the valence shellof an atom is called valence electrons, and there is only one electron presentin the valence shell of hydrogen (1s1). Thus, hydrogen has only one valenceelectron.
Valency of Hydrogen (H)
There are many different ways to find out the valency of anatom which reflects the ability of an atom to bond with other atoms. Valencedescribes how easily an atom or a free radical can combine with other chemicalspecies. The valency of an atom is determined based on the number of electronslost, gained, or shared with another atom at the time of bond formation.
An atom is said to be stable when its outermost shells haveeight electrons (except H & He). If the total number of electrons inoutermost shells is between one to four, the atom has positive valency and ifelectrons are between four to eight, the valency is calculated by subtractingfrom eight and valency will be zero. Atoms having four outermost electronspossess both positive and negative valency, and atoms having eight outermostelectrons, valency will be zero (i.e. noble gases).
Non-metal like hydrogen reaches the stable state (nearestinert gas configuration) by losing one outermost electron. So that the valencyof hydrogen (H) is +1.
We can also find the valency of hydrogen with the help of the periodic table. As hydrogen belongs to group 1 along with the alkali metalswhose valency is always one.
Note: Hydrogen is not an alkali metal. it is a non-metal butplaced in the group of alkali metal in the periodic table based on its valenceelectron. Never forget chemistry is a science of exceptions.
H+ Valence Electrons
Hydrogen-ion H+ means it has lost one electron and has noelectron left on orbitals. The electron configuration of neutral hydrogen is1s1 but in H+ it loses one electron, so it has no electron left on theoutermost shell. Thus, H+ has zero valence electron.
Valency of H+
H+ valency is not zero like noble gases oranything else. Basically, when a hydrogen atom loses one electron, H+ producesand that’s what valency is. So, H+ valency is +1, not zero.