Solids can be classified into three bonding patterns. which of the following is not one of them? a) covalent b) ionic c) metallic d) crystalline

A covalent bond is a bond between two non-metals where they share a pair of electrons, like carbon dioxide (CO2).

An Ionic bonds a bond between metal and a nonmetal where the metal loses electron and becomes positively charged ion (cation) and non-metal gains electrons (from the metal) and becomes negatively charged ion (anion)

The metallic bond is the sharing of many detached electrons (delocalised electrons) between many positive ions in which the electrons freely and randomly flow around (in the material). +NOTE+ delocalised electrons are needed in order for a substance to be able to conduct electricity.

Crystalline bond is you wanted. 

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