Regents Chemistry Exam August 2022
47. Which formula represents a saturated organic compound?
(2) C2H4 (3) C3H4
Explanation: We need to take a look at Table Q on the Reference Table. It has alkanes, alkenes and alkynes and the general formula for each one. Alkanes are saturated organic compounds. Alkenes and alkynes are unsaturated because they have double and triple bonds. The formula for alkanes is CnH2n+2. Let's see which answer choice will work. We plug in the number of carbons in the formula as n to see how many hydrogens we would have, 2n+2. For 2 carbons, we should have 2(2)+2= 6 hydrogens (C2H6) For 3 carbons we should have 2(3)+2 = 8 hydrogens (C3H8).