Which of the following is correct for a compound of the type ZOH ?

Options

A. It is an hydroxide.
B. It is an oxoacid.
C. It is either a hydroxide nor an oxoacid.
D. It is neither a hydroxide nor an oxoacid.

Answer

C

Explanation

If Z is an electropositive element such as alkali or alkaline earth metal, the `Z-O` bond is quite polar and the compound is actually ionic:
`overset(delta)(Z)-overset(delta)(O)-HrarrZ^(+)+OH^(-)`
Thus, hydroxyl compounds of metals are called hydroxides because they can produce hydroxide ions in water to give basic solutions. Oxygen is much more electronegative than most metals, such as sodium. It draws the electrons of the sodium-oxygen bond in `NaOH` (a strong base) so close to itself that the bonding is ionic. Thus, NaOH exists as `Na^(+)` and `OH^(-)` ions even in the solid state and dissociates into `Na^(+)` and `OH^(-)` ions when it dissolves in `H_(2)O`:
`NaOH(s)overset(H_(2)O)rarr Na^(+)(aq.)+OH^(-)(aq.)`
Therefore, alkali and earth metal hydroxides are all bases. If Z is an electronegative element or is in a high oxidation state, it will attract electr5ons, thus, making the `Z-O` bond more covalent and the `O-H` bond more polar. Consequently, the tendency for the H to be donated as an `H^(+)` ion increases:
`Z-overset(delta^(-))(O)-overset(delta^(+))(H)rarr Z-O^(-)+H^(+)`
In this case, the compound behave like an oxoacid.