A piece of chalk can be broken into small particles by hammering but a piece of iron cannot be broken itno small particles by hammering.Which characterstic of matter is illustrated by these observations ?
The particles of matter are attracted to each other by forces of cohesion.
The particles of matter have force acting between them. This force keeps the particles together. The strength of these forces of attraction is lesser in chalk which is the reason why it could be easily broken into small pieces by hammering. But the strength of inter molecular forces of attraction is very strong in iron therefore it could not break and separate the particles by hammering.