Question

Calculate the DU for CHBrO. Solution Br counts as an H and can be ignored, so calculate as though the formula were CH. DU = 1(2)(8) + 2 - 14] = 2. PROBLEM 2.9 Calculate the DU for these formulas and draw two constitutional isomers for each a) CH3,0 b) CHN c) CHF d) CHACIN ®) CHNO Due next Class PROBLEM 2.10 Determine the DU for each of these structures: OCH CH; b) N

Answer 1

To deduce the structure of any given unknown compound with molecular formula, first step is to determine the Degree of unsaturation (DU) For the calculation of DU following formula can be used DU = Number of carbons +1 - (Number of Hydrogens + Number of monovalent atoms (like halogens)- Number of trivalent atoms (like N and P))/2 Oxygens can be ignored while calculating DU 1) C3H73Bro DU = 8+ 1 - (13+1)/2 = 9 - 7 = 2 2.9) a) C10H200 DU = 10 + 1 -(20) 12 = 11 - 10 = 1 b) COHEN DU = 6 +1 -19 -1)/2 = 7 -8 /2 = 7 -4 = 3 C) C7H12F2 DU = 7 +1 - ( 14 + 2)/2 = 8 - 8 = 0 d) CoH CIN DU = 6 + 1 -(8 + 1)-1 /2 = 7 - 10 12 = 7 - 5 = 2 C9H45NO DU = 9 +1 -15 -1/2 = 10 - 16 /2 = 10 - 8 = 2 2.10) b) Chemical Formula: C,H1002 Chemical Formula: CH NO DU = 9 + 1 - (10)/2 = 10 - 5 = 5 DU = 6 + 1-7-1/2 = 7 - 8 12 = 7 - 4 = 3