Video Transcript
Metal cutlery can be coated in silver. Which of the following is not a reason to electroplate cutlery? (A) Enhancing the appearance of the cutlery. (B) Reducing the weight of the cutlery. (C) Protecting the cutlery from damage. (D) Improving the lifespan of the cutlery. (E) Shielding the cutlery from corrosion.
Electroplating is a technique that uses an electrolytic cell to coat an object in a thin layer of metal. This question refers to coating metal cutlery in silver. To accomplish this, we’ll place the metal cutlery in an electrolyte solution. Electrolyte solutions contain ions. When electroplating, we want the electrolyte solution to contain the ions we want to plate with. So to coat the metal cutlery in silver, we need the electrolyte solution to contain silver ions. We’ll also need a piece of the metal we’d like to electroplate with to serve as the other electrode.
To begin electroplating, we’ll connect the cutlery and the silver metal to an external power supply. This will cause a redox reaction to occur in the electrolytic cell. Oxidation will occur at the silver metal electrode. The silver metal will be oxidized to form silver one plus ions and electrons. The electrons travel through the circuit to the other electrode. Silver ions from the solution will be attracted to this electrode. There, the silver ions will accept the electrons and be reduced, forming silver metal, which is deposited onto the cutlery.
We might electroplate cutlery for a number of reasons. Cutlery is often made from cheap metals like iron or steel. By electroplating, we can make this cheap metal cutlery look nicer by coating it in a thin layer of silver or even gold. Since we’re looking for a statement that is not a reason to electroplate cutlery, we can rule out answer choice (A). Electroplating can certainly enhance the appearance of cutlery, transforming it from a cheap metal into something that looks more expensive.
Coating a cheap metal in something like silver has advantages beyond the appearance. Cheap metals are often prone to corrosion, but silver metal is inert, so it won’t corrode. This means we can eliminate answer choice (E). Electroplating cutlery in silver would certainly shield it from corrosion.
Of course, an extra coating of metal will also protect the cutlery from physical damage. As electroplating protects the cutlery from both corrosion and physical damage, electroplating will also improve the lifespan of the cutlery. The only statement that is not a reason to electroplate cutlery is statement (B). When we electroplate cutlery, we coat it in a thin layer of metal. This thin layer of metal would not reduce the weight of the cutlery; rather, it would increase it.
Of the statements we were given, the only one that was not a reason to electroplate cutlery was answer choice (B), reducing the weight of the cutlery.
