Crystalline solids a. have their particles arranged b. randomly exist only at very low temperatures c. exist only at high temperatures d. are usually very soft have highly ordered structures

a. have their particles arranged

Explanation:

A crystalline solid is a solid material with a regular (crystal lattice) or irregular (amorphous) ordered array of its components, being these molecules, atoms or ions. These arrengements are held in place thanks to the atraction between components, they can be ionic compounds held by their charges, metal cations surrounded by a sea of electrons, covalent networks with their atoms covalently bonded or molecular crystals held together by weak intermolecular forces.

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