The statement is true. Covalent molecules are indeed formed when non‑metal atoms share electrons with other non‑metal atoms.

Why this is true

  • A covalent bond is defined as a bond formed by the sharing of one or more pairs of electrons between atoms.
  • Covalent compounds are typically formed between non‑metal atoms that have similar electronegativities and prefer to share electrons rather than transfer them.
  • A common description in basic chemistry is that covalent compounds are made when two or more non‑metal atoms bond by sharing valence electrons.

Small extra note

  • Covalent bonds can occur between:
    • Different non‑metals, like in water (H and O) or carbon dioxide (C and O).
* The same non‑metal, like in O2\text{O}_2O2​ or H2\text{H}_2H2​.
  • So, as written for an introductory chemistry context, the statement is correctly describing how covalent molecules form between non‑metals by sharing electrons.