What is Nickel?
Nickel is the 28th element of the periodic table and is classified as a transition metal. In its pure form, nickel is a silvery-white metal that is very shiny and can have a slight golden tinge. Nickel is commonly used to plate other metals and protect them from corrosion, and is found in many alloys such as stainless steel.
Nickel’s Place in the Periodic Table
It is believed that nickel got its name from a character of German miner mythology. A mischievous sprite named Nickel was thought to personify the fact that copper-nickel ores resisted refinement into copper. Nickel is a transition metal in group 10, and group 10 elements tend to all be very shiny and resistant to tarnish.
- Atomic number: 28
- Symbol: Ni
- Group: 10
- Period: 4
- Number of Protons: 28
- Number of Electrons: 28
- Number of Neutrons: 30
- Atomic Radius: 149 pm
- Atomic mass: 6934
- Number of Isotopes: 5
Properties of Nickel
Nickel is a hard, shiny metal that is most commonly found in ores that look like dull grey rocks. It is resistant to corrosion and very stable in its pure form. It is classified as a transition metal and shares a lot of similar properties with its groupmates like malleability and conductivity. However, while it can conduct heat and electricity, it is not a very efficient conductor, so usually other transition metals are used if these properties are important. Inhaling nickel can lead to agitation of the lungs and naval cavity, but this is rarely a concern. There are certain people who can have mild skin irritation with nickel exposure as well.
Nickel is a hard metal but can be quite malleable and ductile. It is harder than iron, but is on the lower end of density for transition metals. It is also on the lower end as far as melting and boiling points for transition metals.
- Melting Point: 1728 K (1455C)
- Boiling Point: 2913 K (2913C)
- Density: 908 g/cm3
- Phase at Room Temperature: solid
Nickel is relatively unreactive, especially at lower temperatures. It will not react with air or water at room temperature and is resistant to most acids and basic solutions. At higher temperatures, nickel will dissolve slowly in acidic solutions. Nickel can also form a thin coating of nickel (II) oxide which stops corrosion from progressing. It is quite stable and will bond but not readily. Nickel’s relatively low electronegativity contributes to it not bonding frequently.
- Oxidation states: +3, +2, 0
- Specific Heat: 445 J/(kg K)
- Electronegativity: 91
- Heat of Fusion: 2 kJ/mol
- Heat of Vaporization: 378 kJ/mol
- Electron Configuration: [Ar]4s23d8
Nickel has 5 stable isotopes: 58Ni, 60Ni, 61Ni, 62Ni, and 64Ni. The most abundant are 58Ni at around 68% abundance and 60Ni at around 26% abundance. The other isotopes are far less common with 61Ni and 64Ni being around 1% abundance each, and 62Ni being around 3.6% abundance. There are over 25 different known radioisotopes. Most of the stable isotopes have been used to study human absorption of nickel and 60Ni is used for the production of cobalt isotopes that are necessary for bone densitometry.
Alloys and Allotropes
While stainless steel is definitely the most well-known alloy of nickel, there are many other alloys that serve other purposes as well. For example, nickel-chromium alloys that contain at least 15% chromium are very heat-resistant and are used to provide oxidation and carburization resistance at high temperatures. Nickel-copper alloys are commonly used in nuclear submarines because it does well in sea water. Nickel is also commonly mixed with iron (stainless steel is an example) and molybdenum to a lesser extent.
Compounds of Nickel
While nickel is more commonly found in alloy form, there are also several compounds of nickel that are important as well. For example, nickel (Ii) sulfate (NiSO4) is a bright blue salt that is an important source of nickel ions which are needed for electroplating. There is also nickel (II) carbonate (NiCO3) which is a light green salt that can be used as a catalyst. It is most common for nickel to have an oxidation state of +2 so many of its compounds utilize that form.
Interesting Facts about Nickel
- Nickel is occasionally added to glass to give it a green color.
- Researchers have found evidence of nickel being used in various forms as far back at 3500 BCE.
- Nickel is one of the four elements that is ferromagnetic, meaning it is magnetic at or around room temperature.
- Because some people can have slight allergic reactions to nickel, its use in currency has diminished over time.
- Even though nickel makes up only a small percentage of the Earth’s crust, it is the second most abundant element of the Earth’s core, only behind iron.
- Nickel plays a role in the cells of plants and some microorganisms making it an essential element for some plant species.
- About 39% of nickel used each year comes from recycling.
- The nickel-titanium alloy nitinol has the ability to remember its shape. If you bend the metal it will return to its previous shape once it is heated.
- About 65% of all nickel produced goes into stainless steel.
- World War I and II helped increase the demand for nickel significantly because of the increased need for stainless steel.
Occurrence and Abundance of Nickel
Nickel is mined in many parts of the world but it is most commonly mined in Russia, Canada, Australia, Indonesia, China and South Africa. Nickel is commonly found in various ores such as pentlandite, garnierite, and limonite, but it can also be found in its pure form in small amounts. Nickel is quite abundant in the Earth’s crust making up 0.009%. It is also common in meteorites with 1.3% abundance and in the Sun at 0.008% abundance.
Uses of Nickel
Most Notable Uses in General
There are many uses of nickel that are quite common in people’s everyday life. For example, nickel is a component of stainless steel, which is commonly found in kitchen appliances and nickel contributes the property of malleability to this alloy. Other uses for stainless steel include armored plating, boat propellers and turbine blades. Nickel is also used in regular batteries as well as rechargeable batteries and the batteries of hybrid cars. Lastly, nickel is used to form the American coin called the nickel. It is made of 25% nickel and 75% copper.
Most Notable Uses in Science
Nickel is used in a lot of laboratory and medical equipment, mostly in various alloy forms. For example, nickel can be found in surgical implants, medical tools, health care equipment and in dental tools and implants. It’s used in a lot of medical equipment because it is resistant to corrosion and isn’t very reactive.
Discovery of Nickel
Nickel, or at least nickel-containing alloys, have been used for over thousands of years. However, the element was first classified and isolated in 1751 by a Swedish chemist named Axel Fredrik Cronstedt. He originally mistook the ore he was working with as a copper mineral, but was eventually able to isolate the element.
Nickel in the Future
There was a study done in 2017 that confirmed that 78Ni, a non-naturally occurring isotope of nickel, is exceptionally stable. Physicists were running various tests on the isotope using Titan, the most powerful supercomputer in the US. The isotope is incredibly hard to produce, but these studies could shed some light on the understanding of matter’s stability.