Properties of the Fourth-Period of Transition Metal

Fourth-period of transition metal members are:
Sc-Ti - V - Cr - Mn - Fe - Co - Ni - Cu - Zn

• The fourth-period of transition element lies between the IIA and IIIA groups.
• Based on the electron configuration, all four-period transition elements lie in block d in the periodic system.
• All four-period transition elements are metal elements. They have strong metal bonds.
• Solid at room temperature.
• Has high melting and boiling points.
• Can conduct electricity and heat well (conductor)
• Has several oxidation numbers, except Sc and Zn
• Paramagnetic properties.
• Can form complex compounds.

Here is a detailed description of the properties of the four-point of transition element.

1. Metals Properties

• Most of the four-period transition elements have d orbitals that are not fully occupied by electrons. This results in unpaired electrons (isolated electrons).
• The lone electrons can move freely in the crystal lattice to form a very strong metal bond.
• Strong metal bonds on this four-period transition element make it hard and have high density.
• Therefore, the boiling point, the melting point and the mass type of the four-period transition element are high.
• The more unpaired electrons in the d orbitals of the four-point transition element, the stronger the metal bond.
• Among all four-point transition elements, Cr has the highest number of unpaired electrons. Therefore, the metal bond in Cr is the strongest.
• Meanwhile, all d orbitals of Zn (Zinc) atoms are fully charged by electrons. As a result, Zn has no electron outs so that its metal bonds are weakest.

Electrons that can move freely in the metal crystal lattice, also make the transition element can conduct electricity and good heat. If two transition metal ends are given a potential difference, then the electrons can flow. Electrons that flow is called the flow of electricity.

Therefore, many electric cables use copper metal (Cu) as a conductor of electricity.

2. Oxidation number

• An oxidation number is a number indicating the ability of an element to release an electron.
• All four-period transition elements have positive (electropositive) oxidation numbers. This means that all four-period transition elements have a tendency to release electrons.
• Except for Sc and Zn, other four-point transition elements have oxidation numbers of more than one. Unlike the main group elements that have only one oxidation number.
• More than one oxidation number is caused because other than electrons in the skin sub 4s, the electrons in the 3d skin sub can also be released when ionization occurs.
• Electrons on the 3d sub-shell can also be released because the electron energy does not vary much with the electrons in the 4s subshell.
• Sc and Zn have only one oxidation number. This is because the s and d orbital are fully charged by the electrons so that the element becomes harder to release the electrons.
• The more electrons are secluded in the d orbital, the easier it is to remove the electrons. As a result, the element is able to achieve the highest oxidation number.

Consider the following fourth-period transition element oxidation states:
1. Sc = +3
2. Ti = + 2, + 3 and +4
3. V = +1, +2, +3, +4, and +5
4. Cr = +2, +3, and +6
5. Mn = +2, +3, +4, +6 and +7
6. Fe = +2, +3, +4, and +6
7. Co = +2 and +3
8. Ni = +2 and +3
9. Cu = +1 and +2
10. Zn = +2

3. Color

1. Most of the compounds formed by transition metals have color.
2. Colors arise because the energy levels of electrons in the four-period transition elements are almost the same so that electrons can move to higher energy levels by absorbing visible light energy.
3. These shifting electrons are located in the skin sub d. The more electrons in the unpaired d sub, the easier the electron to move from one energy level to another.
4. When at high energy levels, the electrons are unstable and tend to return to their original energy levels. When it returns to its original energy level, the electrons will emit the light radiation we see as the color of the compound.
5. The color will not appear on a four-period transition ion that has no electrons in its d-orbitals or all its d orbital is fully charged by electrons. Example: Sc3 +, Ti2 +, Cu + and Zn2 + ions

4. Magnetic Properties
The fourth-period transition element has 3 magnetic properties.
a. Diamagnetic
It is the property of an element not drawn by a magnetic field. This is because all the electrons in their orbital have been paired.

Example: Zn

b. Paramagnetic
It is the property of an element that is only interested in a bit by the magnetic field. This is due to the unpaired electrons in the element's orbitals. Most of the four-point transition elements are paramagnetic.

Example: Sc, Ti, V, Cr, Mn.

c. Ferromagnetic
They are elements that can be drawn very strongly by magnetic fields. The more unpaired electrons in their elemental orbitals, the stronger the magnetic properties.

Example: Fe has 4 unpaired electrons in its d orbitals so it is paramagnetic.

Share this post