Question

If someone explain how to find these unknowns..And what they are and how you got the answer. I am having a hard time really understanding NMR and IR.. Thanks in advance

Unknowns for 1H NMR Final Report 7) Chemical Formula: CHN IR: weak peak at 3400cm PPM 8) Chemical Formula: CH1204 IR: strong peak 1720cm, peak at 1650cm 2H 4H PPM 9) Chemical Formula: CsH2,02 IR: strong peak at 1750cm 3H

Answer 1

Chemical formula = C8H11N

Sites of unsaturation = (2C+2+N-H-X) / 2

Sites of unsaturation = 4

IR data

3400 cm-1 N-H stretching frequency (presence of amine)

1H NMR data:

7.4 (bs, 1H) Presence of NH

7.01 (t)

6.5-6.70 (m) five aromatic protons

3.40 (q, 2H) CH2 attached to nitrogen and CH3

1.20 (t, 3H) CH3 attached to CH2

All above data indicates following structure

N-ethylaniline Chemical Formula: CgH11N

2) Chemical formula = C8H12O4

Sites of unsaturation = (2C+2+N-H-X) / 2

Sites of unsaturation = 3

IR data

1720 cm-1 C=O stretching frequency (carbonyl group present)

1650 cm-1 C=C stretch frequency (double bond present)

1H NMR data:

6.5 (s, 2H) protons attached to olefin (two equivalent CH)

4.10 (q, 4H) two equivalent CH2 attached to CH3 and oxygen

1.20 (t, 6H) two equivalent CH3 attached to CH2

All above data indicates following structure

diethyl maleate Chemical Formula: CgH1204

2) Chemical formula = C5H10O2

Sites of unsaturation = (2C+2+N-H-X) / 2

Sites of unsaturation = 1

IR data

1750 cm-1 C=O stretching frequency (ester group present)

1H NMR data:

5.0 (m, 1H) CH attached to electron withdrawing groups

2.0 (s, 3H) CH3 attached to carbonyl

1.20 (d, 6H) two equivalent CH3 attached to CH

All above data indicates following structure

isopropyl acetate Chemical Formula: CsH1002