Question

What are soft and hard materials? Give Example

Answer 1

Hint: Before we go into the question, let's have a look at what hard and soft materials are. Hard materials are those that are difficult to crush, chop, distort, or scrape. Crushed, sliced, bent, or scraped soft materials are ones that can be easily crushed, sliced, bent, or scraped.

Complete answer:
Hard materials are materials that cannot be easily crushed, chopped, deformed, or scraped. Iron and glass are two examples. Soft materials are those that can be crushed, sliced, bent, or scraped with ease. Colloids, polymers, liquid crystals, gels, emulsions, foams, and the tissue that makes up the majority of the animal kingdom are just a few examples.
A material's hardness is determined by its crystalline structure, which is uniform and often relatively "tight." This is absolutely true for diamonds, glass, and other hard materials. Hardening steel is accomplished by heating it to a high temperature and then quenching it (cooling it rapidly, to retain the crystal structure of the hot material).
Soft materials have a structure with higher flexibility in the links between molecules or in the crystal structure, allowing them to “give” when a force is applied to them.
Because the material has many links, many softer materials remain strong. For example, rubber in a tyre is quite strong but still fairly soft, and conforms to the little surface structure of a road (which has a harder surface, relative to the rubber). Because the molecules in rubber are long strings that are connected together, this is the case.

Note:
However, we can have soft and hard within a group that is considered “hard” on the whole. Consider steel: you can have an extremely hard piece of steel, such as a drill bit or a tap for producing threads, and a soft piece of steel, which is designed to be machined or bent. If you put one of these in your mattress under the cover, they will be very hard. However, with a hard piece of steel from the first category, the soft steel remains soft and easy to machine. Similarly, we have soft and hard cushions in our mattresses. Even the hardest of those won't ding mild aluminium, let alone mild steel. They're simply different levels of "hardness" within that group.