When orthoboric acid $(H_3BO_3)$ is heated,the residue left is:

Aluminium chloride exists as a dimer,$Al_2Cl_6$,in the solid state as well as in solutions of non-polar solvents such as benzene. When dissolved in water,it gives:

Which of the following is the most basic oxide?

Which one of the following elements does not form triiodide on reacting with iodine?

The formation of $Al_2O_3$ is accompanied by the release of a large amount of energy. This property is utilized in which of the following?

Boron forms covalent compounds due to: