How is the valency of an element in a covalent compound measured?

A covalent compound is-

What is Valency of an element?

F_(2) is a covalent compound.

Give an example of compound in which the oxidation number and valency of an element in the compound are the same .

Which of the Gr-13 elements forms only covalent compounds?

An element forms two compounds X and Y in which the element exhibits the valency of 2 and 3 respectively. What is the ratio of the equivalent masses of the element in the two compound?

Which of the following is not the characteristic of a covalent compound ?

Among the alkaline earth metals, the element forming predominantly covalent compound is :

The atomic number of an element A is 20 and that of another element B is 17. write down their electronic configuration. Will they produce an electrovalent compound or covalent compound? What will be their valencies? What will be the probable formula of the compound formed between them?