Which of the following best describes a possible carbon compound?

a. one carbon atom forms a quadruple bond with another carbon atom.
b. one carbon atom forms a double bond with an oxygen atom and two single bonds with two hydrogen atoms.
c. one carbon atom forms five single bonds with five hydrogen atoms.
d. one carbon atom forms a triple bond with another carbon atom and a double bond with an oxygen atom.

Let's eliminate some options.
Option A: quadruple bonds will most likely not occur between two carbon atoms. so option A is out.
Option B: One double bond with oxygen and two single bonds with hydrogen atoms will give all atoms the "noble gas" or "octet" configuration they desire. Option B is true.
Option C: Carbon is most likely not large enough to have more than eight valence electrons (hypervalent), so option C is out.
Option D: One carbon only has four valence electrons to donate, so the same problem exists as in option C, and the carbon atom will not achieve hypervalence. Option D is out.
Therefore, option B is correct.

Hno3(aq) → h+(aq) + no3−(aq). picture ii best represents the strong acid hno3. strong acids are strong electrolytes

Order of filling levels and sublevels of electrons: 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²3f¹⁴5d¹⁰6p⁶for an element with 5 electrons in the 3d energy level: full configuration: 1s²2s²2p⁶3s²3p³.