The oxide that has a macromolecular structure is silicon dioxide (SiO₂) , also known as silica.

Here's why:

* Macromolecular structure: This means the compound is formed by a continuous network of repeating units, held together by strong covalent bonds.

* Silicon dioxide: Each silicon atom is covalently bonded to four oxygen atoms, and each oxygen atom is bonded to two silicon atoms. This creates a giant, three-dimensional network structure extending throughout the entire crystal.

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