Question

How to find valency of gold?

Answer 1

Hint: The valency of an element can be determined easily by the oxidation number of that element, as valency is the ability of the element to combine with other elements to form a compound. Gold is the element of the d-block element as it is the element of group 11 and the period is 6 so, its atomic number is 79.

Complete answer:
The ability of the element to combine with other elements to form compounds is known as the valency of the element. The valency of an element can be determined easily by the oxidation number of that element. For example, if the valency of the element is 1, then it will either form +1 oxidation state or -1 oxidation state.
So, we have to find the valency of gold. Gold is the element of the d-block element as it is the element of group 11 and the period is 6 so, its atomic number is 79, therefore, there are 79 electrons in a gold atom. Now we can write the electronic configuration of gold as:
$1{{s}^{2}}2{{s}^{2}}2{{p}^{6}}3{{s}^{2}}3{{p}^{6}}4{{s}^{2}}3{{d}^{10}}4{{p}^{6}}5{{s}^{2}}4{{d}^{10}}5{{p}^{6}}4{{f}^{14}}5{{d}^{10}}6{{s}^{1}}$
As we can see that the valence shell of the gold atom is 6 and there is 1electron in this valence shell, so it can lose this electron to form a +1 oxidation state, therefore, having a valency 1.
But there is a more stable valency of gold is 3 than 1 because due to destabilization of the 5d orbital, two electrons from the 5d orbital are also lost forming a +3 oxidation state.

Note:
Some other less stable oxidation states of -1, +2, and +5. But gold is a noble metal and it does not react easily with other metals due to which it is used as ornaments and jewelry.