Q45. Which of the following is the correct Lewis dot formula for H2S?

Background

Topic: Lewis Structures for Molecules and Polyatomic Ions

This question tests your ability to draw and interpret Lewis dot structures, which show the arrangement of valence electrons around atoms in a molecule. For H2S (hydrogen sulfide), you need to determine how the atoms are bonded and how the lone pairs are arranged on the central atom (sulfur).

Key Terms and Concepts

• Lewis Structure: A diagram that shows the bonding between atoms and the lone pairs of electrons in a molecule.

• Valence Electrons: Electrons in the outermost shell of an atom that are involved in bonding.

• Lone Pair: A pair of valence electrons not shared with another atom.

• Bond Pair: A pair of electrons shared between two atoms (a single bond).

Step-by-Step Guidance

1. Count the total number of valence electrons in H2S. Hydrogen has 1 valence electron each, and sulfur has 6.

2. Determine the central atom. Sulfur is less electronegative than hydrogen and can form more bonds, so it is the central atom.

3. Connect each hydrogen atom to the sulfur atom with a single bond. Each bond uses 2 electrons.

4. Subtract the electrons used in bonds from the total to find how many are left for lone pairs.

5. Place the remaining electrons as lone pairs on the sulfur atom. Each lone pair contains 2 electrons.

Try solving on your own before revealing the answer!