an application of electrochemistry in which a sheet metal is coated with a less reactive and most often more expensive metal is?

One application of electrochemistry in which a sheet metal is coated with a less reactive and more expensive metal is electroplating. Electroplating is a process that involves depositing a layer of metal onto the surface of another metal object using an electrochemical cell.

In this process, the less reactive and more expensive metal is used as the coating material, while the sheet metal acts as the substrate. The substrate metal is typically a cheaper and more readily available metal, such as steel or copper, while the coating metal can be gold, silver, platinum, or other precious metals.

Electroplating is commonly used in various industries, including jewelry, automotive, electronics, and aerospace. It serves several purposes, such as enhancing the appearance of the substrate metal, improving corrosion resistance, providing wear resistance, and facilitating solderability.

For example, in the jewelry industry, gold electroplating is often used to coat silver or copper jewelry pieces. This gives them an attractive gold appearance while utilizing a less expensive base metal. Similarly, chrome plating is commonly applied to steel or aluminum automotive parts to enhance their corrosion resistance and aesthetic appeal.

Overall, electroplating is an important application of electrochemistry that allows for the cost-effective and efficient coating of sheet metals with less reactive and more expensive metals.