Question

Food cans are coated with tin and not with zinc because:
A. zinc is costlier than tin
B. zinc has a higher melting point than tin
C. zinc is more reactive than tin
D. zinc is less reactive than tin

Answer 1

Hint:Determine the most important factor that affects the quality of food stored in the container. Eliminate the factors that do not affect the quality of the food.

Complete answer:
Whether zinc is costlier than tin or tin is costlier than zinc, is of less significance. The most important factor in the selection of metal for storage purposes is that when you place food in the container, the quality of food should not be affected. Here, the cost of metal is less significant as you use the same container again and again for several times. So you can rule out options (A).
Whether zinc has a higher melting point than tin, or tin has a higher melting point than zinc, is of less significance. This is because the food that you keep in the container has much lower temperature than the melting point of the container. Hence, you can rule out the option (B).
In the electrochemical series, zinc is placed above tin. This means that zinc is more reactive than tin. Due to this, zinc can react with food. But tin cannons react with food. Due to this, food can be preserved in tin containers but if you keep food in a zinc container, then food will get spoiled.
Thus, food cans are coated with tin and not with zinc because zinc is more reactive than tin

Hence, the option (C) is the correct option.

Note:
The food is usually stored in the container so that it may be consumed later, usually within 24 hours of the preparation of the food. For example, you prepare food today afternoon and you want to consume it tomorrow afternoon, then you can store the food in the container.