Ru or Ruthenium is the transition metal element of the d block element having a partially filled 4d orbital. Let us explain about Ruthenium in detail.
Ru is the heavier transition metal of the 4d series and it is present in the same group as iron. Ruthenium is a hard metal and brittle in nature and appears silvery-white metallic in color, which is categorized as a platinum group. It is neutral on acid but reactive towards halogen.
Like palladium powder, Ru can be used as a catalyst in many organic synthesis reactions. To increase its ductility, platinum and palladium are added to it. Now we will discuss the basic chemical properties of Ruthenium with proper explanation in this article.
1. Ruthenium symbol
Symbols are used to express the element by using one or two letters of the English or Latin alphabet of the chemical name. Let us predict the atomic symbol of Ruthenium.
“Ru” is the atomic symbol of Ruthenium as the name of the element starts with the R letter in the English alphabet but the letter R is already taken for the alkyl group in organic chemistry. So we use the first two letters of the word Ruthenium instead of the first letter to distinguish the element.
2. Ruthenium group in the periodic table
Vertical lines or columns of the periodic table are referred to as a respective group of the periodic table. Let us predict the group of Ruthenium in the periodic table.
Ru is placed in the 8th vertical series of the periodic table by its atomic number by Mendeleev. So, it is the 8th group element and is distinguished on the precipitation table.
3. Ruthenium period in the periodic table
A horizontal line or row of the periodic table where every element is placed by its last principle quantum number is called a period. Let us predict the period of Ruthenium.
Ru is placed in the 5th period as it contains more than 36 electrons, which are placed in the above 4th period. Therefore the remaining electrons are placed in the 5th period of the periodic table. It is placed before the lanthanide series.
4. Ruthenium block in the periodic table
The orbital where the valence electrons of the element are present is called the block of the periodic table. Let us predict the block of the Ruthenium.
Ruthenium belongs to the d block element as the valence electrons are present in its d orbital. It contains s, p and d orbitals but the outermost orbital of Ru is d because of 4 principle quantum number.
5. Ruthenium atomic number
The value of Z, known as the atomic number, is the total number of electrons. Let us find the atomic number of Ruthenium.
The total atomic number of Ruthenium is 44 which means it has 44 protons because the number of protons is always equal to the number of electrons. For this reason, they become neutral due to the neutralization of equal and opposite charges.
6. Ruthenium Atomic Weight
The mass of the element is called weight which is measured with respect to some standard value. Let us calculate the atomic weight of Ruthenium.
The atomic weight of Ruthenium is 101 on the 12C scale, which means the atomic weight of carbon is 101/12th part. But the actual value is 101.07, which is the average value of different isotopes of Ruthenium.
7. Ruthenium Electronegativity according to Pauling
Pauling electronegativity is the power to attract any other element for that particular atom. Let us predict the electronegativity of Ruthenium.
The Pauling electronegativity is 2.2 for the Ru, which means it is close to electronegative as its value is greater than 1 and the same value as iron as it belongs to the same group. So, it has higher ability to attract any other element like other transition elements, and form highly positively charged cations.
8. Ruthenium atomic Density
The number of atoms present per unit volume of any atom is called the atomic density of that respective element. Let us calculate the atomic density of Ruthenium.
The atomic density of Ruthenium is 12.2 g/cm3 which means the weight of atoms per unit volume of Ru is calculated to be 12.2. The atomic weight is divided by the standard volume value of the element by Avagardo’s value of 22.4 L at STP.
- Atomic density = atomic mass / atomic volume
- The atomic mass or weight of the Ruthenium atom is 101.07 g which is established
- The volume of the Ruthenium molecule is 22.4 liter at STP as per Avogardo’s calculation
- So, the atomic density of the Ruthenium atom is, 101.07/(8.28) = 12.2 g/cm3
9. Ruthenium melting point
Changing to a liquid state from its solid state at a particular temperature is called the melting point of that particular element. Let us find the melting point of Ruthenium.
The melting point of Ruthenium is 23340 C or 2607K temperature because Ru has a hexagonal close-packed lattice in the crystal form. When it exists in a solid state, it needs greater energy to break that crystal, so it has a higher melting point like heavier transition metal.
10. Ruthenium boiling point
Boiling point is that point when the vapor pressure of an element becomes equal to its atmospheric pressure. Let us find the boiling point of Ruthenium.
The boiling point of Ruthenium is 41500 C or 4423K because it has a higher melting point. So it needs more energy than the melting point for boiling. If the element does not exist in liquid form then it cannot be boiled off. Also, it is a metal element so it needs more energy for its gaseous state.
11. Ruthenium Van der Waals radius?
Van der Waal’s radius is the distance between the center of two atomic spheres attached together. Let us find Van der Waal’s radius of Ruthenium.
The Van der Waal’s radius for Ru is 205 pm as it contains 3d, and 4d orbitals, and the 3d and 4d orbitals have a shielding effect on the nucleus to outermost electrons. So, it has a greater nucleus attraction towards the outermost shell and the radius will decrease because 3d and 4d orbital are subject to poor shielding effect.
- Van der Waal’s radius is calculated by the mathematical formula considering the distance between two atoms, where atoms are the sphere in shape.
- Van der Waal’s radius is, Rv = dA-A / 2
- Where RV stands for Van Waal’s radius of the molecule of spherical shape
- dA-A is the distance between two adjacent spheres of the atomic molecule or summation of the radius of two atoms.
12. Ruthenium ionic radius
The summation of the cation and anion is called the ionic radius of the element. Let us find the ionic radius of Ruthenium.
The ionic radius of Ru is 205 pm which is the same as van der Waal’s radius, because in the ionic form it has the same ionic value.
13. Ruthenium isotopes
Elements having the same number of electrons but different mass numbers are called isotopes of the original element. Let us discuss the isotopes of Ruthenium.
Ruthenium has 41 isotopes based on their neutron numbers which are listed below:
- 87Ru
- 88Ru
- 89Ru
- 90Ru
- 91Ru
- 91mRu
- 92Ru
- 93Ru
- 93m1Ru
- 93m2Ru
- 94Ru
- 94mRu
- 95Ru
- 96Ru
- 97Ru
- 98Ru
- 99Ru
- 100Ru
- 101Ru
- 101mRu
- 102Ru
- 103Ru
- 103mRu
- 104Ru
- 105Ru
- 106Ru
- 107Ru
- 108Ru
- 109Ru
- 110Ru
- 111Ru
- 112Ru
- 113Ru
- 113mRu
- 114Ru
- 115Ru
- 116Ru
- 117Ru
- 118Ru
- 119Ru
- 120Ru
Stable isotopes are discussed in the below section among 41 isotopes of Ruthenium:
| Isotope | Natural Abundance | Half-life | Emitting particles | No. of Neutron |
| 96Ru | 5.54% | stable | N/A | 52 |
| 97Ru | Synthetic | 2.9 d | €, γ | 53 |
| 98Ru | 1.87% | stable | N/A | 54 |
| 99Ru | 12.76% | stable | N/A | 55 |
| 100Ru | 12.60% | stable | N/A | 56 |
| 101Ru | 17.06% | stable | N/A | 57 |
| 102Ru | 31.55% | stable | N/A | 58 |
| 103Ru | Synthetic | 39.26 d | β, γ | 59 |
| 104Ru | 15.62% | stable | N/A | 60 |
| 106Ru | Synthetic | 391.59 d | β | 61 |
Only 10 isotopes are stable of Ru among all isotopes, so they emit radioactive particles. 97Ru, 103Ru, and 106Ru are synthetically prepared isotopes of Ruthenium among all and the rest of them are naturally obtained.
14. Ruthenium electronic shell
The shell surrounding the nucleus as per principal quantum number and holding the electrons is called an electronic shell. Let us discuss the electronic shell of Ruthenium.
The electronic shell distribution of Ruthenium is 2 2 6 2 6 10 2 6 7 1 because it has s, p, and d orbitals around the nucleus. Since it has more than 36 electrons and in order to arrange 44 electrons, it needs 1s,2s,2p,3s,3p,3d,4s,4p,4d, and 5s orbitals.
15. Ruthenium electron configurations
According to Hund’s rule electrons are distributed to the respective orbitals which are known as electronic configurations. Let us discuss the electronic configuration of Ruthenium.
The electronic configuration of Ru is 1s22s22p63s23p6 3d104s2 4p64d75s1 according to Hund’s rule and the Aufbau principle, as it has 44 electrons. To fill all the 44 electrons, Ru needs s, p, and d orbitals having the 1st,2nd, 3rd, 4th, and 5th orbitals.
- Due to exchange energy electrons enter first in 5s orbital then 4d.
- Where the first number stands for the principal quantum number
- The letter is for orbital and the suffix number is the number of electrons.
- But many elements have more principal quantum numbers depending on the number of electrons.
- Xe has 54 electrons, so the remaining electrons are present after the noble gas configuration.
- So, it is denoted as [Kr]4d75s1.
16. Ruthenium energy of first ionization
First I.E. is the energy required for the removal of electron from the valence orbital of its zero oxidation state. Let us predict the first ionization of Ruthenium.
The first ionization value for Ru is 710 KJ/mol because the electron was removed from the half-filled 5s orbital, due to poor shielding effect and outermost orbital so the energy required to remove an electron from 5s is lesser than the other orbital of Ru. Also, 5s has a lower shielding effect.
17. Ruthenium energy of second ionization
Second I.E. the energy required for the removal of one electron from the available orbital from the +1 oxidation state. Let us see the second ionization of Ruthenium.
The 2nd ionization energy of Ru is 1620 KJ/mol which occurred from its 4d orbital and the energy of 4d orbital is higher due to the poor shielding effect it experiences more attraction towards the nucleus. So, when an electron is removed excited state it required higher energy than the previous one.
Generally, 2nd ionization energy is greater than 1st ionization energy because it occurs from a more excited state or inner orbital.
18. Ruthenium energy of third ionization
Removal of third electron from the outermost or pre-ultimate orbital of an element having a +2 oxidation state is the third I.E. Let us predict the third I.E. of Ruthenium.
The third ionization energy for Ru is 2740 KJ/mol because the third ionization occurs from the partially filled 4d orbital. But after the removal third electron, it gains half-filled stability so, the energy for the removal of the third electron is higher but not expected to be high.
19. Ruthenium oxidation states
During bond formation, the charge that appears on the element is called the oxidation state. Let us predict the oxidation state of Ruthenium.
Ru shows variable oxidation states from -2 to +6, but the most common oxidation state of Ru is -2, -6, +2, +3, and +4, where it can form stable compounds like RuO4. Due to the presence of 4d, and partially filled 5s orbitals, it can show different oxidation states to gain stability.
20. Ruthenium CAS number
CAS number or CAS registration for any element is used to identify the element which is unique. Let us know the CAS number of Ruthenium.
The CAS number of the Ruthenium is 7440-18-8 which is given by the chemical abstracts service.
21. Ruthenium Chem Spider ID
Chem Spider ID is the particular number for a particular element given by the Royal Society of Science to identify by their character. Let us discuss it for Ruthenium.
22390 is the Chem Spider ID for Ruthenium which is given by the RSC (royal society of chemistry). By using this number we can evaluate all the chemical data related to the Ruthenium atom. Like the CAS number, it is also different for all elements.
22. Ruthenium allotropic forms
Allotropes are elements or molecules with similar chemical property but different physical properties. Let us discuss the allotropic form of Ruthenium.
Ru has no allotropic form like other transition metals because it cannot show the catenation property like carbon elements. It has only more than half filled 4d orbital to show different chemical properties.
23. Ruthenium chemical classification
Based on the chemical reactivity and nature, the elements are classified into some special class. Let us know the chemical classification of Ruthenium.
Ruthenium is classified into the following categories:
- Ru is a heavier transition element
- Ru is a catalyzing agent
- Ru is also classified as reactive based on the reaction tendency towards carbonyl.
- Ru is more ductile and carry electricity as per electrical conductance.
24. Ruthenium state at room temperature
The physical state of that particular atom is the state at which an element can exist at room temperature and standard pressure. Let us predict the state of Ru at room temperature.
Ruthenium exists in a solid state at room temperature because it has a crystal lattice that it adopts in the hexagonal structure, where van der Waal’s force of attraction is so high. Also, the layers are present over one another, so it is soft in nature.
25. Is Ruthenium paramagnetic?
Paramagnetism is the tendency of magnetization in the direction of the magnetic field. Let us see whether Ruthenium is paramagnetic or not.
Ruthenium is paramagnetic in nature due to the presence of three unpaired electrons in the valence or outermost 5d orbital and the magnetic value will be 3.87 B.M. which is a spin-only magnetic value. It has a molar magnetic susceptibility value of +39 ×10−6 cm3/mol.
Conclusion
Ru is a 4d transition metal element, due to the presence of four unpaired electrons it is subject to Jann-Teller distortion in its geometry. It can form many organometallic compounds and due to more d electrons, it can bind with soft ligand which can be sigma donor and π acceptor like carbonyl. Also acts as mildly acidic oxide due to higher oxidation state.
Hi……I am Biswarup Chandra Dey, I have completed my Master’s in Chemistry from the Central University of Punjab. My area of specialization is Inorganic Chemistry. Chemistry is not all about reading line by line and memorizing, it is a concept to understand in an easy way and here I am sharing with you the concept about chemistry which I learn because knowledge is worth to share it.