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Chrome plating is also commonly used in automotive parts. Common household items that are manufactured with chrome plating are doorknobs, bathroom taps, and lighting fixtures. The result is a thin layer of chromium being left on top of either a metal or alloy substrate. It is accomplished by passing an electric current between two electrodes immersed in an electrolyte bath with chromic acid. Chromium is a great choice for plating as it is lustrous, hard, and naturally resistant to tarnishing and corrosion. Electroplating with ChromiumĮlectroplating, also known as electrodeposition, is the process of plating one metal onto another to prevent corrosion or enhance the appearance. Naturally occurring chromium is a mix of four isotopes. It is the first element in the periodic table to violate the Aufbau principle. Chromium chemistry has some things in common with vanadium, manganese and molybdenum.Ĭhromium’s electron configuration is 3d 5 4s 1. It is the first element of group 6, along with molybdenum and tungsten. It lies to the left of manganese and the right of vanadium on the periodic table. Hexavalent chromium or chromium is extremely toxic as it can cause cancer, destroy red blood cells, and give rise to genetic mutations.Ĭhromium is a hard, silvery transition metal with atomic symbol Cr and atomic number 24.

Trivalent chromium is a vital micronutrient and aids the efficiency of insulin in individuals who struggle with glucose intolerance.Southern Africa and Zimbabwe supply 99% of the world’s chromite which is composed of iron(II) oxide and chromium(III) oxide.75% of chromium produced today is used in alloys such as stainless steel to protect and shine base metals such as copper or zinc.

Chromium is named after the Greek word ‘chroma’ or ‘chromos’ which translates to ‘color’ and references the element’s ability to compose colorful compounds.

Find out more about this radiant transition metal down below! Interesting Facts about Chromium! Moreover, it has a rich chemistry and is well known for creating colorful compounds and is often used to both protect and polish other metals through a process called electroplating. The end point of a potassium dichromate(VI) titration isn't as easy to see as the end point of a potassium manganate(VII) one.The element chromium (Cr) can be found in group 6 on the periodic table. However, the color is made difficult by the strong green also present. This gives a violet-blue color in the presence of excess potassium dichromate(VI) solution. There are several such indicators - such as diphenylamine sulfonate.

These change color in the presence of an oxidising agent. With potassium dichromate(VI) solution you have to use a separate indicator, known as a redox indicator. Unfortunately potassium dichromate(VI) solution turns green as you run it into the reaction, and there is no way you could possibly detect the color change when you have one drop of excess orange solution in a strongly colored green solution. As soon as you add as much as one drop too much, the solution becomes pink - and you know you have reached the end point. As you run the potassium manganate(VII) solution into the reaction, the solution becomes colorless. Potassium manganate(VII) titrations are self-indicating.

The main disadvantage lies in the color change.

That means that you don't get unwanted side reactions with the potassium dichromate(VI) soution. Potassium manganate(VII) oxidises chloride ions to chlorine potassium dichromate(VI) isn't quite a strong enough oxidising agent to do this.

Potassium dichromate(VI) can be used in the presence of chloride ions (as long as the chloride ions aren't present in very high concentration).

That isn't true of potassium manganate(VII). That means that it can be made up to give a stable solution of accurately known concentration.

Potassium dichromate(VI) can be used as a primary standard.

There are advantages and disadvantages in using potassium dichromate(VI). You will see that the chromium(III) sulfate and potassium sulfate are produced in exactly the right proportions to make the double salt.