INFRARED SPECTROSCOPY

Transcription

1 SPECTROSCOPY LEVEL TEACHERS' GUIDE IR SPECTRA OF LIQUIDS (Rvis ) Tis b is im w s-y misy m v fis-y sus. I us piip bjivs, sus su b fmii wi fui gups suu fmus f mus bsis f gi mu. Uss sus giv ug iui IR spspy, y wi ppi v us p f w mus bsb ii. T b su b p by iui bsis f spspy. T piips f spspy b iu usig Sp-20, by ig IR spspy f fims. T b is sig v sus pfmig P 1 wi s usig isum. P 1 is iy i gups f w fu. P 2 my b sigy i pis. Tugu pu sus su b f b wi s. NOTE: Yu my w giv yu sus is f P 2 subss s m iify i uw fm is is. T fw-up qusis f b g i f isig iffiuy. S ssig y s wi pppi v pi xpi f yu sus. Tis b wi fi i uiuum wi suy f pysi ppis, gi mpus fui gups, mgi ii. IR spspy my s b iu s sp ui i f isf pquisis v b v. PRE-LAB DISCUSSION A umb f pis wi b fusig sus, s sm im bf p m us sm f bsi migy. Spifiy ss fwig: Absb ps: T sp sus wi b xmiig wi b smi sp. W ii is bsb, is s i ii smi. Tis is xibi by ww fi f p i gi f spum. Tis ww

2 SPECTROSCOPY fi is bsb p. Sm my w gu i is ug vy. Ty v isiy b f s ps. Ty u s b bspi bs. (I x f us f sip, musi smb.) I my b simp xpi si m, p. Wvumbs vsus wvgs: T wvumb is w m sus. I is us igby wi fquy, bu wvumbs y fquis. Ty iy ppi fquy f gy f bspi. Wvumbs us i iu f fquy gy s m f vi. Cu, f xmp, fquy spig IR wvg f 6200 m: Tis is g ivi xpi umb. IR spspiss, gizig wvg fquy ivsy v us wvumb, ip f wvg i m. Rip m ppi fquy uis f m vi siz. If yu i i is imp sus us m by vb fiii, w ug sm xmps usig quis y su b fmii wi. S wvg i m, v i m ip. Dms s wvg iss wvumb ss, ppi fquy gy. P smi: A iii isiy f ii ii s smp. Sm f i is bsb, mi is smi. T p smi is i f w. Isiy f bsb: W ipig sp, sus wi b s quiivy mi isiy f p - w big i is! Ty su giz g mgiu f bspi p, g bsb ( ss smi). T ms us sig isiy i is b sg (s), mium (m) w (w).

3 Sw yu sus sm IR sp w bsbs vy wi fui gups, b sgs mi msss. Sw m sp wi ms iff bw, f xmp, C-H s i (sp 3 b) (sp 2 b) iffs simiiis mg vius by mpus. Af f pquisis v b v, sp y pi ivy f isum v ipi f smp sp. Us vs f sp v sus piip i mpig b i s y wi b usig. Dms gi ivv. Ty wi v mu g g f suss gig i b if y mfb wi pu ufmii ms v b mysifi. PREPARATION Twy-fu sp (six ss f fu) pvi wi is b f us i P 1. Ts sp f mpus f wi v fiy siy iifib fui gup. Sm f sp i gup my v mm ms mg m. T s sp f P 2 wi s b pvi s w s uw iquis. T iquis wi b suppi i gss bs wi pp wi b s us. TIME ALLOTMENT A ss su g ug b ps i bu fu 50 miu b pis. SAFETY / DISPOSAL Sus su w gvs gggs uig is b. Wi wi viy f gi mpus, sm my b my bsb, ims piy gs sm sus. Dpig umb f sus ivv ig sv us, ig f iqui smps ig s ps u b i. Tiifu ws w is ss zus im. 3

4 VARIATIONS I my b f is bi spum f s p sw sus ps ivy sp IR ii i is gi f spum. Ps v b us my sw bsbs u miis fm ig, bspi f mis impp ig. SAMPLE RESULTS Yu my w b fiy ib i gig. Tis wi iy b sus' fis xpsu usig i yig iffi p fm. Ty su m wy wi fig f usfuss f isum, gii f sm pi ppiis. Bw spss qusis. ANSWERS TO PRELAB QUESTIONS 1. Typi fiiis f : umix wi yig, uiu, sig. Avgs f smps : si ppi bus mixig is qui; xus ps fm svs; sv ffs. 2. Equis : E = / ë õ = / ë A mpis bw if visib iis b bu: fquy gy wvg visib g g s if ss ss g 3. A fui gup is piu gm f ms i mu wi imps isi s f ppis mu. T fui gups gi mu is b i b ssifi i g yps fmiis f gi mpus. 4. Wig gvs wi p pv: iquis fm big bsb ug si; s ps fm bsbig i misu fm figips. 4

5 5. T quus sui wi issv s ps! ANSWERS TO FOLLOW -UP QUESTIONS 1. Rf y f sp i P Rf y f sp i P Rf y f sp i P Asws wi vy. 5. A si is i-ig vi, iig w bsbig mi (smig ygspi) us y s subss. 6. T w pssibiiis f is fmu imy, CH 3 -O-CH 3 y, CH 3 CH 2 OH. T p 1200 m -1 bs f O-H s bv 3200 m -1 iis fis mpu is. T s mpu, xibiig p is y. 7. P smi is i f smi ii ii ii. Mmiy, %T = I / I x 100, w I is smi isiy I is iii isiy. 8. T bgu b fi s u iis i wi smig is xpi - i is s, vim bw su f ii. I is w isum "ss" w smp is ps. Absb fm bgu i IR sp is u pimiy w vp b ixi. Si bsb i is gi f spum y b msu fm suig gs i ip mm, imi mus su s N 2 O 2 ibu bgu. If bsb u bgu w sub, ipi f spum wu b mpi by ii ps. 9. L sus b iv. T bs sps is gss is sp IR ii. Tis u b ms wi w mms, f wi is 5

6 isi s s ub, s qu is fm is bub. T isi ub wi is sm mpu. Tis u s b ms by ig spum f gss si. 10. F sps. 11. NC bgis bsb sgy bw 500 m T vus giv i wvumbs ip f wvg i ims (ip ims). Giv 4000 m -1 (4000/m), ip v ms. 13. T ip b is sg ub b. A sg b gy sps g vibi gy. 6

7 KEY - PART 1 SAMPLE SETS OF SPECTRA PROVIDED BY THE CHEMOBILE Ts ms spig umbs f f sp. Gup A (g) Gup B (pup) 1 -bu 1 yx 2 bmbz 2 ispy 3 buy py 3 2-p 4 bzy 4 3-mip Gup C () Gup D (bu) 1 isppy 1 yx 2 2-p 2 ispy 3 1-py 3 x 4 2-bu-1-4 bzy Gup E (g) Gup F (vi) 1 i i 1 y 2 yx 2 bmbz 3 p 3 mybz 4 1-py 4 1-pp 7

8 KEY - PART 2 FUNCTIONAL GROUP IDENTIFICATION CHART Uw Cmpus p CH 3 (CH 2 ) 5 CH 3 1-py CH 3 (CH 2 ) 4 C CH 2-p CH 3 (CH 2 ) 4 COCH 3 bzy C 6 H 5 CHO yx C 6 H 11 OH y CH 3 CO 2 C 2 H 5 i i CH 3 (CH 2 ) 7 - CH=CH(CH 2 ) 7 - CO 2 H buy py 2-bu-1- C 6 H 5 O(CH 2 ) 3 CH 3 CH 3 CH=CHCH 2 O H yx C 6 H 10 y i m i y m i s b i 8

9 Uw Cmpus bmbz C 6 H 5 B 3- mip (C 2 H 5 ) 2 CHNH 2 ispy (CH 3 ) 2 - CHCH 2 CH 2 OH -bu CH 3 (CH 2 ) 3 OH my bz C 6 H 5 CH 3 CH 3 COCH 3 10-ui i CH 2 =CH(CH 2 ) 8 - COOH isppy (CH 3 ) 2 CHOH 1-pp CH 3 CH 2 CH 2 OH y i m i y m i s b i NOTE: Tis b is jus p ify fui gups f yu. Yu fuy si w yu gig us i. Csi bspis by ps f mu (xuig pimy fui gup) my s b ps. Hwv, f xmp, gi mis wu sy isppy is, NOT. KEY - PART 2 UNKNOWN LIQUID NUMBERS Ts umbs spig iqui uws. 9

10 Uw Uw Numb Iiy Numb Iiy 1 p 13 3-mip 2 1-py 14 ispy 3 2-p 15 -bu 4 bzy 16 2-p 5 yx 17 mybz 6 y 18 7 i i 19 yx 8 buy py ui i 9 2-bu-1-21 ispy 10 1-py 22 isppy 11 yx 23 bmbz 12 bmbz 24 1-pp 10