A glass container and a process for chemically modifying a surface portion of a glass container using an ion-exchange process. At least a portion of the glass container is immersed in or in contact with an aqueous electrolyte solution comprising salts of at least one group IA alkali metal and having a temperature of about 75 degrees Celsius such that exchangeable alkali metal ions in a surface portion of the glass container are exchanged or replaced by alkali metal ions in the electrolyte solution. The alkali metal ions that replace the exchangeable ions in the surface portion of the glass container have either a smaller or a larger atomic radius than the exchangeable ions.