Chlorine
As we know the only electrons which take part in chemical bonding are the valence electrons. Therefore, in given options we will look for an atom having greater umber of valence electron. In order to find the number of valence electrons we will draw the electronic configuration of each element and will find the number of electrons in valence shell.
Oxygen:
8 = 1s², 2s², 2p⁴
There are 6 electrons in valence shell (i.e. 2) of Oxygen.
Chlorine:
17 = 1s², 2s², 2p⁶, 3s², 3p⁵
There are 7 electrons in valence shell (i.e. 3) of Chlorine.
Neon:
10 = 1s², 2s², 2p⁶
There are 8 electrons in valence shell (i.e. 2) of Neon but it will not react with Hydrogen because of its stability and complete octet.
Nitrogen:
7 = 1s², 2s², 2p³
There are 5 electrons in valence shell (i.e. 2) of Nitrogen.
Except Neon, all three atoms will react with \hydrogen and among these three Chlorine has the greatest number of valence electrons and hence, it is the correct answer.
The element that has the most electrons available to react with hydrogen is [tex]\boxed{\text{D.\;nitrogen}}[/tex].
Further Explanation:
Octet Rule
Each and every element tends to gain stability. For this purpose, it bonds with other elements in such a way that it obtains eight electrons in its valence shell. This rule is known as the octet rule. Almost all elements form bonds in accordance with this rule. Hydrogen does not obey the octet rule, but it follows the duplet rule. It contains only 1s orbital so it can accommodate a maximum of two electrons.
Hydrogen has an atomic number of 1 and its electronic configuration is [tex]1{s^1}[/tex].
A. The atomic number of oxygen is 8 so its electronic configuration is [tex]1{s^2}2{s^2}2{p^4}[/tex]. It is two electrons short of the noble gas configuration of neon. So it can form one double bond with the hydrogen atom.
B. The atomic number of chlorine is 17 so it has an electronic configuration of [tex]1{s^2}2{s^2}2{p^6}3{s^2}3{p^5}[/tex]. It is just a single electron short of the noble gas configuration of neon. So it can form one single bond with the hydrogen atom.
C. The atomic number of neon is 10 and its electronic configuration is [tex]1{s^2}2{s^2}2{p^6}[/tex]. It has a complete octet so it has no tendency to form bonds with any other element. So it does not make bonds with the hydrogen atom.
D. The atomic number of nitrogen is 7 and it has an electronic configuration of [tex]1{s^2}2{s^2}2{p^3}[/tex]. It needs three more electrons to complete its octet and achieve a noble gas configuration of neon. So it can form three single bonds with the hydrogen atom.
Since nitrogen can form maximum bonds with the hydrogen atom, it has the maximum number of electrons that are available to react with hydrogen.
Learn more:
Answer details:
Grade: High School
Chapter: Chemical bonding and molecular structure
Subject: Chemistry
Keywords: hydrogen, nitrogen, chlorine, neon, oxygen, octet, duplet, three single bonds, electrons.
