Question

Which is more hard, sponge or iron?

Answer 1

Hint:Hardness of the materials depends on the packing of its particles and intermolecular forces among the particles of the substance.

Complete answer:
Every matter is made up of particles. These particles are held with intermolecular forces and possess thermal energy. More is the intermolecular force of attraction. The particles are tightly packed and they cannot get deformed by applying external force. These substances are difficult to compress and are called as hard materials and those are easy to compress are called soft because in hard materials, forces of attraction between the atoms are high, and closely packed there is least free space between the atoms in hard materials.
Sponge possess large intermolecular spaces and least intermolecular force of attraction. So, it is soft and can be deformed by applying a small force. But iron is a metal with high interaction force and least thermal energy. So, it is hard as compared to sponge.
Hence, iron is very hard as compared to sponge. Also iron has more density as compared to spong.

Note:: Iron is the chemical element with Fe as its symbol. It belongs to the group \[8,\] its atomic number \[26.\] Iron makes up \[5\% \] of the Earth’s crust and is one of the most abundantly available metals. It is obtained from the minerals hematite and magnetite. It can also be obtained from taconite, limonite, and iron is the most used of all the metals. Iron is an essential part of hemoglobin. Sponge is an amorphous substance. Sponge is artificial as well as natural.