Chemistry

Question Analysis
This question involves the identification of bond types in different compounds and the distinction between compounds with pure covalent bonds and those containing ionic bonds (or mixed bonds).

Key Concept Explanation
Covalent bonding occurs when two atoms share one or more pairs of electrons. The shared electrons are attracted to the nuclei of both atoms, which holds the atoms together in a covalent bond. And covalent bonds typically form between nonmetals.

Step-by-step Solution
1. Recall the condition for compounds with only covalent bonds: Composed of nonmetals only; no metal elements involved.
2. Analyze each compound:
KNO₃: K⁺ (metal) and NO₃⁻ (polyatomic ion) → ionic + covalent
HBr: H an...