Question

the molecule hit is: answer: a homonuclear b heteronuclear c monatomic d nonpolar e a radical

Explanation:

• Homonuclear: A molecule composed of atoms of the same element. Here, \( \text{HI} \) has two different elements (\( \text{H} \) and \( \text{I} \)), so this is incorrect.
• Heteronuclear: A molecule composed of atoms of different elements. \( \text{HI} \) has \( \text{H} \) (hydrogen) and \( \text{I} \) (iodine), which are different elements.
• Monatomic: A molecule that consists of a single atom. \( \text{HI} \) has two atoms (\( \text{H} \) and \( \text{I} \)), so this is incorrect.
• Nonpolar: For a diatomic molecule to be non - polar, the two atoms must be the same (so that the electronegativity difference is zero). Since \( \text{H} \) and \( \text{I} \) have different electronegativities (\( \text{H}: 2.20\), \( \text{I}: 2.66\)), \( \text{HI} \) is polar.
• A radical: A radical has an unpaired electron. In \( \text{HI} \), \( \text{H} \) has \( 1\) valence electron and \( \text{I} \) has \( 7\) valence electrons. They form a covalent bond (\( \text{H}-\text{I} \)) with all electrons paired.

Answer:

B. heteronuclear