The 24th element in the periodic table is chromium. The element of group-6 is a chromium and its symbol is ‘Cr’. Chromium is a transition element. Therefore, the valence electrons of chromium are determined differently.

You are watching: How many valence electrons in chromium

The last shell(orbit) of a chromium element has only one electron but its valence electrons are not one. This article discusses in detail the valence electrons of chromium. Hopefully, after reading this article you will know in detail about the valence electrons of chromium(Cr).


How many electrons and protons does chromium(Cr) have?

The nucleus is located in the center of the atom. Protons and neutrons are located in the nucleus. The atomic number of chromium is 24. The atomic number is the number of protons.

That is, the number of protons in chromium(Cr) is twenty-four. Electrons equal to protons are located in a circular shell outside the nucleus. That is, a chromium atom has a total of twenty-four electrons.

What are the valence electrons of chromium(Cr)?

The 1st element in group-6 is chromium and this is the d-block element. The elements in groups 3-12 are called transition elements. The valence electron is the total number of electrons in the last orbit.

But in the case of transition elements, the valence electrons remain in the inner shell(orbit). This is because the electron configuration of the transition elements shows that the last electrons enter the d-orbital.


*
*
*
*
*
*
Valency and valence electrons of chromium

Also, valency is determined from the electron configuration of the element in the excited state. The electron configuration of chromium excited state is Cr*(24) = 1s2 2s2 2p6 3s2 3p6 4s1 3dx2 3dy2 3dz1.

Here, The electron configuration of chromium(Cr) shows that its last shell has two unpaired (4s1 3dz1) electrons. Therefore, the valency of chromium is 2. The valency depends on the bond formation. Chromium 2 and 3 valency’s are used most of the time.

How many valence electrons does chromium ion(Cr2+, Cr3+) have?

The electron configuration of chromium shows that the last shell of chromium has one(4s1) electron and the d-orbital has a total of five electrons. There are two types of chromium ions. The ionic state of the element changes depending on the bond formation. Cr2+ and Cr3+ ions exhibit more than chromium atoms.

Cr – 2e– → Cr2+

Here, The electron configuration of chromium ion(Cr2+) is 1s2 2s2 2p6 3s2 3p6 3d4. The electron configuration of chromium ion shows that chromium ion(Cr2+) has three shells and that shell has twelve electrons (3s2 3p6 3d4). For this, chromium ion(Cr2+) have a total of twelve valence electrons.

Cr – 3e– → Cr3+

On the other hand, The electron configuration of chromium ion(Cr3+) is 1s2 2s2 2p6 3s2 3p6 3d3. The electron configuration of chromium ion(Cr3+) shows that chromium ion has three shells and that shell has eleven electrons (3s2 3p6 3d3). Here, the valence electrons of the chromium ion(Cr3+) are eleven.

Compound formation of chromium

Chromium participates in the formation of bonds through its valence electrons. We know that the valence electrons in chromium are six. This valence electron participates in the formation of bonds with atoms of other elements.

The electron configuration of chlorine shows that the valence electrons of chlorine are seven. The chromium atom donates its valence electrons to the chlorine atom and the chlorine atom receives those electrons.

See more: What Is A 1902 Penny Worth Money, 1902 Indian Head Penny Value

As a result, chlorine acquires the electron configuration of argon. Chromium(III) chloride(CrCl3) is formed by the exchange of electrons between one atom of chromium and three atoms of chlorine. Chromium(III) chloride(CrCl3) is ionic bonding.