Question

What is a substance formed by the chemical combination of two or more elements in definite proportions?

Answer 1

It is called a compound

Explanation:

Compounds are substances formed when two or more elements are combined that are always present in fixed ratios. The elements are bonded together either through covalent or ionic bonding.

Covalent bond is a kind of bonds where atoms in the compound are sharing their outermost electrons to achieve stability.

Ionic bond is also a kind of bonds where atoms in the compound are losing and gaining each others' valence electron (transfer of electrons) to form and achieve stability.