Answer:
Whichever one of your answer options does not have a molcular formula of C5H12. It's hard for me to tell what the answer options show.
Explanation:
Pentane is a 5-carbon alkane, meaning all carbon atoms are connected by single bonds. In pentane, all the bonds not occupied by carbon atoms are occupied instead by hydrogen atoms. In general, a quikc way of figuring out the molecular formula for an alkane is CnH(n+2), where n is the number of carbon atoms. If you have a molecular formula that does not follow this rule, either there is a different number of carbon atoms, or there is a double or triple bond between carbon atoms such that there are fewer bonds available for hydrogen atoms to occupy.
