Question

Find the valence factor for bases $Ca(OH{)}_2$

• A. 3 or 2
• B. 0 or 2
• C. 1 or 2
• D. (a) and (b) above.

Answer 1

The correct option is C 1 or 2

In case of acid-base reaction, the valency factor is the actual number of $H^{+}$ or $O{H}^{-}$ replaced in the reaction. The acid or base may contain more number of replaceable $H^{+}$ or $O{H}^{-}$ than actually replaced in reaction.
Valency factor for base is the number of $O{H}^{-}$ ion replaced by per molecule of the base.
$Ca(OH{)}_2$ can replace 1 or 2 $O{H}^{-}$ depending on the reaction.
Hence valency factor is 1 or 2.