Question

What is the valency of $\mathrm{Ca}$ in the compound $\mathrm{CaO}$?

Answer 1

Valency

• The valency of an atom refers to its ability to combine with other atoms.
• The valency of an element determines the number of bonds that an atom can make as part of a complex.
• The electrons in the atom's outermost orbit are referred to as valence electrons.

Valency of $\mathrm{Ca}$ in the compound $\mathrm{CaO}$

• In the compound, $\mathrm{CaO}$, $\mathrm{Ca}$ has a valency of $2$.
• Calcium is electropositive in nature.
• For completing its octet, calcium atom need to lose two electrons to form calcium cations showing valency of $2$,
• Now it needs the presence of a matching anion, namely the oxide anion, with a valency of $2$ that must balance the positive charge on the calcium cation.

Thus, the valency of $\mathrm{Ca}$ in the compound $\mathrm{CaO}$ is $2$.