please help as soon is possible The following two questions are OPTIONAL: 18-24

Question

please help as soon is possible The following two questions are OPTIONAL: 18-24 and 18-25; 19-6 (bonus). IR relased: IR-1: How many vibrational modes do Nz molecules have?How about Hizo? IR- Label the MAJOR pealks incach IR spoctrum aandaplain the corresponding stretchingbending (eg. CH stretching, o H bending, enc.) 0,6 NIST Chemistry webBook (http:/wwetbook.nist.govlchemistry) NIST Chemistry Webeook (httpdiwebbook.nist.gov/chemistry) BUTANONC ACID IR-3: Use NIST Chemistry Webbook and locane the IR spectra of the following organic molecules and then repeat the exercises in IR-1 (identifying the MAJOR peaks). (i) Hexane: 2) Ethyl alcohol: G) 1-Heptene: propionaldehyde. NMR-2: Predict the 'H and BCNMR.fall the possible isomers of bromobutane.

Explanation / Answer

IR-1 : N2 is a linear molecule so it has,

3N-5 modes of vibration

= 3 x 2 - 5

= 1 mode of vibration

H2O is a non-linear molecule having, 3N-6 modes of vibration

= 3 x 3 - 6

= 3 modes of vibration

IR-2 : Major peaks in the IR spectrum of,

Cyclohexene : 2850-2950 cm-1 for sp3 -C-H stretch ; 3020 cm-1 for sp2 =C-H stretch ; 1620-1680 cm-1 peaks for C=C stretch

Toluene : 3000-3100 cm-1 peaks for sp2 =C-H stretch ; 1500-1600 cm-1 for aromatic C=C stretch

2-butanone : 2850-2950 cm-1 for sp3 -C-H stretch ; 1750 cm-1 for C=O stretch

Butanoic acid : 2500-3200 cm-1 broad peak for O-H of -COOH ; 1710 cm-1 for C=O stretch

IR-3 : Major peaks in IR spectrum of,

(1) Hexane : 2850-2950 cm-1 sp3 -C-H

(2) ethylalcohol : 3350 cm-1 O-H

(3) 1-heptene : 3040 cm-1 sp2 =C-H ; 1630 cm-1 C=C

(4) benzaldehyde : 3020 cm-1 sp2 =C-H ; 2720 and 2850 cm-1 for aldehydic group

NMR-1 : predict NMR of,

Butane

1H : 0.9 ppm triplet, 6H ; 1.1 ppm sextet 4H

13C : 9 ppm ; 14 ppm

Ethanol

1H : 1.2 ppm CH3 (triplet) ; 2.6 ppm (singlet, 1H) -OH ; 3.8 ppm (quartet) CH2

13C : 18 ppm ; 58 ppm

Propionaldehyde

1H : 1.1 ppm (triplet) CH3 ; 2.2 ppm (quartet) 2H ; 9.9 ppm (singlet) CHO

13C : 35 ppm ; 44 ppm ; 64 ppm

NMR-2 Isomers of bromobutane

1-bromobutane

1H : 0.9 ppm CH3 (triplet) ; 1.1 ppm CH2 (sextet) ; 1.4 ppm CH2 (quintet) ; 3.8 ppm (triplet) CH2

2-bromobutane

1H : 1.1 ppm (triplet) CH3 ; 1.4 ppm (doublet) CH3 ; 1.6 ppm (quintet) CH2 ; 4.1 ppm (sextet) CH

2-methyl-2-bromopropane

1H : 1.4 ppm (singlet) 9H

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

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