Which of the following best describes the Lewis dot structure of neutral carbon tetrahydride (CH4)?

• A. Carbon atom in the center with one triple bond to one hydrogen atom and three single bonds to three hydrogen atoms.
• B. Carbon atom in the center with four single bonds to four hydrogen atoms, and no lone pairs on carbon.
• C. Carbon atom in the center with two double bonds to two hydrogen atoms, and two lone pairs on carbon.
• D. Carbon atom in the center with four single bonds to four hydrogen atoms, and two lone pairs on carbon.

Answer: (B)

Verified step by step guidance

1. Recall that the Lewis dot structure represents the valence electrons of atoms and how they are shared or paired in a molecule.
2. Determine the total number of valence electrons: Carbon has 4 valence electrons, and each hydrogen has 1 valence electron. For CH4, total valence electrons = 4 + (4 × 1) = 8 electrons.
3. Arrange the atoms with carbon in the center because it is less electronegative and can form multiple bonds, and place the four hydrogen atoms around it.
4. Distribute the electrons to form bonds: Each hydrogen needs 2 electrons to complete its duet, so form four single bonds between carbon and each hydrogen atom, using 8 electrons total.
5. Check the octet rule for carbon: Carbon shares 8 electrons through these four single bonds, satisfying its octet without any lone pairs, confirming the correct Lewis structure is carbon with four single bonds to four hydrogens and no lone pairs.