The charge of tin (Sn) is an intrinsic property that affects its properties, reactions, and applications. Tin can also move between two different charges, +2 and +4. This makes it a little confusing to know which is the correct charge of the metal.
This ability of tin to exhibit two different charges makes it unique. It also influences the reactions it undergoes and its applications, as mentioned earlier. The charge of tin depends on how many electrons of the outermost shell it loses.
Continue reading to learn about the charge of Sn, its reactions, and its applications in various industries.
Properties of tin (Sn)
- Tin is a metal in the carbon family. It sits between germanium and lead on the periodic table
- Tin is a soft silvery white metal with a bluish tinge. It is a scarce metal but it is not rare
- It has an atomic number of 50 and an atomic weight of 118.69
- It has an electronic configuration of [Kr]4d105s25p2 with 2, 8, 18, 18 & 4 electrons in its shell
- The metal has two allotropes; the silvery-white (beta) tin and the gray (alpha) tin. β-tin is stable at room temperature and above while α-tin exists at a lower temperature
- Furthermore, β-tin is metallic tin with a body-centered tetragonal crystal structure. α-tin, on the other hand, is nonmetallic, brittle, and has a diamond cubic crystal structure like diamond and silicon
- Tin is a solid at STP with a melting point of 449.47°F (231.93°C) and a boiling point of 4,716°F (2,602°C)
- Neat room temperature, the silvery white allotrope has a density of 7.265 g/cm3 and the gray allotrope has a density of 5.769 g/cm3. At the melting point, the density drops to 6.99 g/cm3
- A common use of tin is for plating the inside of steel cans, bearings, and solder
What is the charge of Sn?
Tin can have a +2 or +4 depending on how it reacts. To form Sn2+, tin loses two electrons from its 5s2 or 5p2 orbitals. To form the Sn4+ ion, tin loses all four electrons in the 5s2 and 5p2 orbitals.
Sn2+ is the more common tin ion but it is not as oxidized as the Sn4+ ion.
What is the charge of Sn in tin oxides?
Tin forms two categories of oxides because it can exist as Sn2+ or Sn4+. Tin(II) oxides are known as stannous oxides while tin(IV) oxides are known as stannic oxides.
In both categories, the charge remains +2 or +4.
Stannous oxides
- Tin(II) oxide, SnO
- Stannous monoxide, Sn2O
Stannic oxides
- Tin(IV) oxide, SnO2
- Stannic nitrate, (Sn(NO3)4)
- Tin oxide halides
What are the reactions of Sn?
With air
Tin(II) reacts with oxygen and forms stannous oxide, SnO. Tin(IV) also reacts with oxygen but the reaction produces cassiterite, SnO2.
2Sn + O2 ———> SnO
Sn + 2O2 ———> SnO2
With water
Tin does not react with water at room temperature. When it heats to steam, it forms tin(II) oxide and gives off hydrogen gas.
Sn + 2H2O ———> SnO2 + 2H2
With halogens
Tin reacts with halogens to form tin halides. It reacts with both tin(II) and tin(IV) to form tin(II) halides and tin(IV) halides.
Tin(II):
- Sn + F2 ———> SnF2
- Sn + Cl2 ———> SnCl2
- Sn + Br2 ———> SnBr2
- Sn + I2 ———> SnI2
Tin(IV):
- Sn + 2F2 ———> SnF4
- Sn + 2Cl2 ———> SnCl4
- Sn + 2Br2 ———> SnBr4
- Sn + 2I2 ———> SnI4
With sulfur
The reaction between tin and sulfur is exothermic and happens rapidly. The two elements combine to form tin sulfide. The reaction is as follows:
Sn + S ———> SnS
With acids
Tin reacts with hydrochloric acid, sulfuric acid, and concentrated nitric acid to form salts of tin and release gas. Tin(II) reacts well with hydrochloric acid and sulfuric acid while tin(IV) reacts with nitric acid.
- Sn + 2HCl ———> SnCl2 + H2
- Sn + H2SO4 ———> SnSO4 + H2
- Sn + 4HNO3 ———> H2SnO3 + 4NO2 + H2O
With alkalis
Tin(IV) reacts with alkalis to form stannates of the metal in the alkali. Sn4+ readily reacts with KOH and NaOH.
Sn + 2KOH + H2O ———> K2SnO3 + 2H2
Applications of tin in its charged state
Tinning
Tin is used for tin plating or tinning the surface of metals, such as steel or copper to prevent rust. Tin plating also enhances the physical appearance of food packaging cans.
Companies that produce electronic components also employ tinning to make these materials rust-resistant and solderable. Additionally, tin plating is an essential step in the manufacture of automotive parts and roofing materials.
Alloying
Materials made with alloys made from tin show remarkable properties. They can withstand the temperatures of soldering and they are useful for making solders. Tin-based alloys are major materials used to make sculptures, coins, and some tableware.
Glass, ceramic, and jewelry industries
Tin oxides and tin-based alloys are used in the production of glass and decorative jewelry. Tin oxide is responsible for the “opal glass” effect that is seen in some types of glass. The milky appearance is a result of the scattering of light by tin oxide particles.
Medicine
Tin(IV) and organotin compounds are potential anticancer agents. They are employed via various mechanisms as chemotherapy drugs. However, there is a limitation to their use because of their toxicity.
FAQs
What is the nuclear charge of Sn?
The nuclear charge of tin is the total positive charge in the nucleus of the atom. This is also equal to the number of protons and the atomic number. Therefore, the nuclear charge of tin is 50.
How many protons and neutrons are in tin ion?
Tin ions, Sn2+ and Sn4+, contain the same number of protons and neutrons in the neutral tin atom. Both ions contain 50 protons and 69 neutrons.
What elements does tin react with?
Tin readily reacts with oxygen, hydrogen, carbon, nitrogen, sulfur, and halogens. It also forms compounds with tellurium, bismuth, gallium, lead, zinc, thallium, and selenium.
Which elements will tin not react with?
Tin does not readily react with noble gases, lithium, sodium, potassium, palladium, beryllium, platinum, cesium, magnesium, calcium, and gold.
Conclusion
Tin can lose two or four electrons in its outermost shell to form Sn2+ or Sn4+. Sn2+ is more common and more stable than Sn4+. However, both cations are equally useful to chemical processes and several industries.
The charge on tin makes it useful in alloying, production of semiconductors, and cancer treatment. Tin-based compounds are also used as catalysts in organic reactions. The charge of tin influences the reactivity and selectivity of the catalyst.
Another property that measures the charge of tin is its effective nuclear charge, Zeff. Check out this guide to learn how to calculate the Zeff of tin using Slater’s rule.
Thanks for reading.