Question

name the compound $ce{al_{2}o_{3}}$.\
\
\bigcirc aluminum oxide\
\bigcirc aluminum(ii) oxide\
\bigcirc dialuminum trioxide\
\bigcirc aluminum trioxide\
\bigcirc aluminum(i) oxide

Explanation:

To name the compound \( \text{Al}_2\text{O}_3 \), we first identify the elements: aluminum (Al) and oxygen (O). Aluminum is a metal that forms a cation with a fixed oxidation state of +3 (since it's in group 13, it typically loses 3 electrons). Oxygen is a non - metal that forms the oxide ion (\( \text{O}^{2 - } \)). For ionic compounds with metals in fixed oxidation states (like aluminum, which has only one common oxidation state in its compounds), we use the common name. The formula unit is composed of 2 aluminum ions and 3 oxide ions, but when naming, we use the name of the metal followed by the name of the non - metal with its ending changed to -ide. So, it is named aluminum oxide. The other options are incorrect: Aluminum(II) oxide would imply a +2 oxidation state for Al, which is wrong. Dialuminum trioxide and aluminum trioxide are not the correct naming conventions for this ionic compound (we don't use prefixes in the same way as for molecular compounds here since it's an ionic compound with a metal of fixed oxidation state). Aluminum(I) oxide would imply a +1 oxidation state for Al, which is also incorrect.

Answer:

A. Aluminum oxide