Metals are malleable because of weak bonds between atoms. this allows planes of atoms to slide past one another and into new positions. some alloys retain their malleability while others become more rigid. consider the diagrams in model 1.
predict which type of alloy would result in a more rigid substance. justify your reasoning.

Interstitial alloy because the atoms are closely packed in this lattice which will restrict their movement.

Explanation:

Interstitial alloy is a type of alloy formed when an atom of relatively small radius is inserted into an an interstitial “hole” in a metal lattice. The main difference between interstitial and substitutional alloys is that in substitutional alloy, there is the substitution of one metal atom for another similar metal atom while in interstitial alloy, the small metal atoms are inserted into the holes of the metal lattice.  Since in the Interstitial alloy, the atoms are closely packed in this lattice which will restrict their movement, then this type of alloy will form a more rigid substance.

i do not get it   at all