Step by step text solution for Which one of the following statements is incorrect for HCP packing arrangement in 3D? a) The coordination no.is 12 .b)It has 74% packing efficiency. c) All the octahedral void are fully present inside the unit cell. D) All the tetrahedral void are fully present inside the unit cell. by CHEMISTRY experts to help you in doubts & scoring excellent marks in Class 11 exams.