MATERIALS WITH PRIMARY ATOMIC BONDS Metallic HHHH (Mee( electron“gmy or“ cloud”) °C:C:C:C -metals 100 kcalmol HHHH onIc Covalent (attraction (Shared- pair electrons oo of positive polymers ++ and negative ions biological macromolec, -ceramIcs (eg. proteins -calcium phosphates -200 kcal/mol 10-20 kcal/molMATERIALS WITH PRIMARY MATERIALS WITH PRIMARY ATOMIC BONDS ATOMIC BONDS + + + + + + _ _ _ _ Metallic Metallic (electron “glue” (electron “glue” or “cloud”) or “cloud”) -metals -100 kcal/mol 100 kcal/mol C C C C C C C C H H H H H H H H H H H H H H H H Ionic (attraction (attraction of positive of positive and negative ions) and negative ions) -ceramics ceramics -calcium phosphates calcium phosphates -10 -20 kcal/mol 20 kcal/mol Covalent Covalent (shared (shared - pair electrons) pair electrons) -polymers polymers -biological biological macromolec macromolec. (e.g., proteins) , proteins) -200 kcal/mol 200 kcal/mol M M M M M e M - e - e - e - e - e - e - e - e - e - e - e - e - e -