What is the charge of Rb when it forms an ion?
When neutral atoms develop a charge, what is obvious to the eye is the integer and the sign. However, what goes on within the atom is a dance of protons and electrons.
A loss of electrons gives the element a positive charge because it has more protons than electrons. On the other hand, electron gain gives the element a negative charge because it has more electrons than protons. Metals naturally undergo electron loss and form cations, while nonmetals undergo electron gain and form anions.
The center of this article is rubidium (Rb), a metal in group 1. I will discuss its ionic charge, nuclear charge, and the reactions it undergoes.
Properties of rubidium
- Rubidium is the fifth alkali metal in group 1. It lies between potassium and cesium in the periodic table
- It has an atomic number of 37 and an atomic weight of 85.46 g/mol
- It has an electronic configuration 1s22s22p63s23p63d104s24p65s1 with 2, 8, 18, 8 & 1 electrons in its shells
- Rubidium is a soft, grey-white solid at STP with a boiling point of 1,270°F (688°C) and a melting point of 102.74°F (39.30°C)
- At room temperature, the metal has a density of 1.532 g/cm3. The density drops to 1.46 g/cm3 at its melting point
- Rubidium is the 23rd most abundant element on the Earth. It is present as rubidium oxide in minerals like leucite, pollucite, and carnallite.
- It is commercially sourced from lepidolite, potassium chloride, and some potassium minerals
What is the charge of rubidium ion?
Rubidium is a group one element. It loses the single electron in its outermost shell and forms Rb+, which implies that it has a +1 charge.
What is the nuclear charge of rubidium?
The nuclear charge of rubidium is 37. The nuclear charge of rubidium is the total number of protons in its atom, which is the same as its atomic number.
What is the effective nuclear charge of rubidium?
The effective nuclear charge, Zeff, of rubidium is the difference between the nuclear charge and the shielding constant.
That is, Zeff = Z – S
Z = 37
S can be determined using Slater’s rule.
Assign electron values to the electrons according to the electronic configuration: 1s22s22p63s23p63d104s24p65s1
The electrons in 1s22s22p63s23p63d10 shield 1 and the electrons in 4s24p6 shield 0.85. However, the electron in 5s1 (the electron of concern) has no shielding effect.
Therefore,
S = (8 x 0.85) + (1 x 28)
= 34.80
Zeff = 37 – 34.80
Zeff = 3.80
What is the charge of Rb in RbOH?
The charge of Rb in RbOH, rubidium hydroxide, is +1.
The charge of OH- is -1. If you substitute this value into the chemical formula,
Rb + (-1) = 0
Rb = +1
What is the charge of Rb in RbMnO4?
RbMnO4, rubidium permanganate, contains one cation and one anion. MnO4– is the anion with a -1 charge. If you input this value into the chemical formula and equate it to 0, you can determine the charge of Rb.
Rb + (-1) = 0
Rb = +1
What is the charge of Rb in rubidium nitrate?
The charge of Rb in Rubidium nitrate, RbNO3, is +1.
Here’s how to get this value:
The charge of NO3– is -1
What is the charge of Rb in rubidium sulfide?
In rubidium sulfide, Rb2S, the oxidation state of S is -2. The charge of rubidium can be determined by substituting the oxidation state of S into the chemical formula and equating it to 0.
That is,
2Rb + (-2) = 0
2Rb = +2
Rb = +1
What are the reactions of rubidium?
With water
Rubidium reacts violently with water, just like most alkali metals. It is an exothermic reaction that produces hydrogen gas rubidium hydroxide and heat.
2Rb (s) + 2H2O (l) ———> 2RbOH (aq) + H2 (g)
With hydrogen
Rubidium forms rubidium hydride with hydrogen gas.
2Rb (s) + H2 (g) ———> 2RbH (s)
With oxygen
The reaction of rubidium with oxygen is very slow. Oxygen tarnishes the grey-white surface of the metal and forms an oxide. The first tarnish is a protective covering that preserves the metal underneath from further reaction with oxygen.
At high temperatures, rubidium oxidizes to rubidium superoxide, RbO2.
Rb (s) + O2 (g) ———> RbO2 (s)
With the halogens
Like every other alkali metal, rubidium forms corresponding halides with members of the halogen family. It reacts with fluorine, chlorine, bromine, and iodine to form rubidium fluoride, chloride, bromide, and iodide.
- 2Rb (s) + F2 (g) ———> 2RbF (s)
- 2Rb (s) + Cl2 (g) ———> 2RbCl (s)
- 2Rb (s) + Br2 (g) ———> 2RbBr (s)
- 2Rb (s) + I2 (g) ———> 2RbI (s)
With hydrochloric acid
When rubidium reacts with hydrochloric acid, it forms the alkali halide salt, rubidium chloride, alongside hydrogen gas. The chemical reaction is represented as follows:
2Rb (s) + 2HCl (aq) ———> 2RbCl (s) + H2 (g)
With nitrogen
Rubidium can also react with nitrogen gas to form a nitride.
3Rb (s) + N2 (g) ———> Rb3N (s)
FAQs
What compounds does rubidium form with oxygen?
When rubidium reacts with oxygen, it forms rubidium oxide (Rb2O), rubidium superoxide (RbO2), and rubidium peroxide (Rb2O2). The formation of Rb2O and RbO2 are exothermic reactions that cause heating.
Can rubidium form anions?
Anions of alkali metals are not very common because they’d rather form cations. Metals are more prone to losing than gaining electrons. Rubidium may form anions but it is rare.
How many protons are in rubidium ion?
Rubidium ion, Rb+, contains 37 protons, 48 neutrons, and 36 electrons. The neutral rubidium atom contains the same number of protons and neutrons but 37 electrons. The reduction in the number of electrons is because the atom lost one electron to form an ion.
Conclusion
The ability of an element to lose or gain electrons influences its ability to participate in chemical reactions. Rubidium gets into most reactions in its ionic form. Rubidium ion is also responsible for its various applications in different industries.
Rb+ ion plays vital roles in different catalysis and synthesis reactions. Rubidium-based compounds have electronic properties that support accuracy and light detection in atomic clocks and photomultiplier tubes.
You can also leave about the charge and reactions of cesium, the succeeding metal to rubidium.
Thanks for reading.