Question

$N{H_4}^+$, $C{l^-}$ and ${H^+}$ are monovalent ions. (State whether the statement is true or false.)
a) True
b) False

Answer 1

Monovalancy means having one unpaired electron that can readily form a bond with another atom. So check for one unpaired electron in the given ions. If all of them have only one unpaired electron or vacant electron then they are monovalent.

Complete answer:
The ions $N{H_4}^+$ , $C{l^-}$ and ${H^+}$ all have their charge as one.
From this we can understand that all of their valency is one and that they can form a single bond by either gaining or losing an electron.

**Hence, we can conclude that all the given ions are monovalent and hence the given statement is true i.e. option a.

Additional information: **
Monovalency as the name suggests, is having one valence electron or univalence. Atoms or molecules that are monovalent can form one ionic or covalent bond. Some examples for monovalent atoms or molecules or ions are Hydrogen, sodium ion, potassium ion etc. Similarly, divalent and trivalent compounds have two valence electrons or three valence electrons respectively.

Note:
In the given ions, $N{H_4}^+$ has a positive charge on it and hence has one valence electron readily available to form a bond with an anion by taking up one electron from it. In $C{l^-}$ ion, Chlorine has a negative charge on it so it has one valence electron readily available to form a bond with a cation by losing its electron. Similarly, in ${H^+}$ there is one valence electron that can form a bond.