What happens to solid when mixed with other solid

The atoms in a solid tend to attract each other, more than they are attracted by another substance, which I suppose is one definition of a solid. So strictly speaking, atoms from one solid will not get caught up in the atomic bonding structure of another solid just by placing them together.

3 1/4 %

explanation:

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.