Why is it that elements combine to form compounds?

Explanation:

Almost all the elements combine to form compounds, although the reactivity may vary from element to element. These combinations take place because almost all the elements are unstable. ... By gaining or losing electrons, ionic compounds are produced. Sharing of electrons results in the formation of covalent compounds

the child will have heterozygous dominant chromosomes as characters of his father are dominant over the characters of his mother.

the child is heterozygous