3. The conversion of an alkene in exothermic. The amount of energy released (kno

Question

3. The conversion of an alkene in exothermic. The amount of energy released (known as the heat of hydrogenation) depends on the stability of the double bond undergoing hydrogenation; the more stable the double bond, the lower (less exothermic) the to an alkane via catalytic hydrogenation (with H2 and Pd-C) is always heat of hydrogenation. Alkene Type" ethene (CH2=CHz) monosubstituted cis disubstituted geminal disubstituted trans disubstituted trisubstituted tetrasubstituted | least stable = 7 32.8 kcal/mol -30.1 kcal/mol -28.6 kcal/mol -28.0 kcal/mol 27.6 kcal/mol -26.9 kcal/mol 26.6 kcal/mol 2 most stable 1 This data is for isolated alkenes. Conjugated alkenes are lower energy (more stable) and release less energy upon hydrogenation Select three pairs of compounds with approximately equal heats of hydrogenation. Write the letters for each pair on the lines below. (1.5 pts) (i

Explanation / Answer

(b) and (h) Both compounds have 2 double bonds that are disubstitued and non conjugated.

(d) and (g) Both compounds have 2 double bonds one is disubstitued and other is trisubstitued. The double bond are conjugated.

(c) and (i) Both compounds have 1 double bonds that is tetrasubstitued .

Related Questions

Navigate

• Browse (All)
• Browse 3
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.