What types of elements typically combine to form covalent compounds?
metals
nonmetals and metals
metalloids and metals
nonmetals

ionic bonds can form between nonmetals and metals, while covalent bonds form when electrons are shared between two nonmetals.

Explanation:

Nonmetals  typically combine to form covalent compounds.

Explanation:

The octet rule states that the atoms of the elements bond each other in the attempt to complete their valence layer with eight electrons. That is to say, the atoms will tend to yield or share electrons to complete eight electrons in the valence layer.

In other words, the objective is to have the closest noble gas electronic configuration, thus having the last complete electron layer and acquiring stability.

The covalent bond is the chemical bond between atoms where electrons are shared, forming a molecule. Covalent bonds are established between non-metallic elements. These elements have many electrons at their outermost level (valence electrons) and tend to gain electrons in order to comply with the octet rule mentioned and be stable. The shared electron pair is common to the two atoms and holds them together.

Then, nonmetals  typically combine to form covalent compounds.

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