Correct Option
The correct option is Gold plating : Silver ornaments.
Explanation
Electroplating is the process of depositing a thin layer of one metal over another to enhance appearance, prevent corrosion, or improve surface properties.
Statement-wise Analysis
- Chromium plating : Food storage cans – Incorrect. Chromium plating is primarily used for corrosion resistance and decorative finishes in automobile parts and sanitary fittings, not for food storage cans.
- Zinc plating : Car bumpers and taps – Incorrect. Zinc plating is mainly used to protect iron and steel from rusting (galvanisation), whereas car bumpers and taps are commonly chromium plated.
- Tin plating : Bridges and automobiles – Incorrect. Tin plating is used for food storage cans due to its non-toxic nature, not for large structural applications like bridges or automobiles.
- Gold plating : Silver ornaments – Correct. Gold plating is commonly applied to silver ornaments to enhance appearance and prevent tarnishing.
Key Takeaway: Electroplating applications depend on the specific protective, decorative, or chemical properties of the metal being deposited.