I. Quartz is a mineral composed of silicon and oxygen atomsin a continuous framework of SiO4, silicon-oxygen tetrahedralwith each oxygen being shared between two tetrahedra, whichform the overall chemical formula of SiO2. Few types of quartzerystals possess piezoelectric properties. These quartz crystalspossess an electric potential upon the application of mechanicalstress. Thus, statement I is correct. II. The group 14 tetrachlorides except CCl4 are easilyhydrolyzed through water. It happens due to the unavailablevacant d- orbital's and steric crowding due to presence of fourCl atoms around C atom which don't allow water molecule toapproach antibonding orbitals of C-Cl bonds. Thus, statement IIis correct.