chuyen de nhan biet va tach chat cuc hay

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Chuyn 1: Nhn bit Tch cht

1. S

2. Nhn bit 2.1. V c 2.1.1. n cht 2.1.1.1. Nhn bit kim loi a. Nhng phn ng c trng ca kim loi

Cht cn nhn bit Thuc th Hin tng Phng trnh phn ng

Kim loi kim v kim th H2O

Dung dch trong + H2 (i vi Ca cho dung dch

c) M + nH2O M(OH)n + 2

n H2

Li (Li+) Tm ln a Ngn la ta

Mui

NHN BIT TCH CHT

V C HU C

N CHT

HIROCACBON DN XUT

Ancol

Axit Este

Amino axit

HP CHT

Ankin

Ankan

Ankaien

Anken

NO KHNG NO

THM

Xicloankan

Kim loi

Phi kim

Baz

Axit

Oxit Anehit Xeton

Amin

Cacbohirat

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K (K+) Tm Na (Na+) Vng Ca (Ca+) da cam Ba (Ba+)

Pt, ri t trn n kh khng

mu Vng lc

Nguyn t lng tnh:

Be, Zn, Al, Cr

Dung dch OH- (NaOH,

Ca(OH)2) Tan + H2

M + (4-n)OH- + (n-2)H2O MO2n-4 +

2n H2

M + (4-n)NaOH + (n-2)H2O Na

n-4MO2 + 2n H2

Pb HCl Kt ta trng + H2 Pb + 2HCl PbCl2 + H2

HNO3 long Kh NO khng

mu 3Cu + 8HNO3

3Cu(NO3)2 + 2NO + 4H2O HNO3 c Kh NO2 mu nu

Cu + 4HNO3 Cu(NO3)2 + 2NO2 +2H2O Cu

t trong O2 Mu (Cu) Mu en

(CuO) 2Cu + O2 2CuO

Au

Hn hp HNO3 c v HCl c t l th tch 1:3

Tan + NO Au + HNO3 + 3HCl AuCl3 + NO + 2H2O

Ba Dung dch H2SO4 long Kt ta trng v

H2 Ba + H2SO4long BaSO4 + H2

b. Mt s bi tp tiu biu: Bi 1: Bng phng php ha hc, hy phn bit bn kim loi sau: Al, Zn, Cu, Fe. Bi 2: Dng phn ng ha hc nhn bit tng kim loi sau: Al, Ca, Mg v Na. Bi 3: C 5 mu kim loi: Ba, Mg, Fe, Ag, Al. Nu ch c H2SO4 long (khng c dng

bt k cht no khc k c qu tm, nc nguyn cht) c th nhn c nhng kim loi no? Bi 4: Ch dng mt ha cht, nu phng php nhn bit 4 mu kim loi sau: Mg, Zn, Fe,

Ba. Bi gii

Bi 1: Al, Zn, Cu, Fe Ly mt t ha cht lm thuc th: - Cho H2SO4 c ngui vo 4 kim loi:

- Ch c Cu, Zn phn ng: Cu + 2H2SO4 c CuSO4 + SO2 + 2H2O Zn + 2H2SO4 c ZnSO4 + SO2 + 2H2O

- Sau , Zn v Cu c phn bit bng HCl long, nh dung dch HCl long vo hai mu, mu no c si bt kh l Zn, mu khng tc dng l Cu.

Zn + 2HCl ZnCl2 + H2 - Hai mu Al v Fe cn li, cho tc dng vi dung dch NaOH, mu no tan trong dung

dich NaOH l Al, mu khng phn ng l Fe. 2Al + 2NaOH + 2H2O 2NaAlO2 (dd) + 3H2


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Bi 2: Al, Ca, Mg v Na Ly mt t ha cht lm thuc th: Cho nc vo 4 mu thuc th, hai mu phn ng l Ca, Na. Hai mu khng tc dng vi

nc nhit thng l Al v Mg. Ca + 2H2O Ca(OH)2 + H2 2Na + 2H2O 2NaOH + H2

Tip theo, thi kh CO2 vo 2 l dung dch va to thnh, l no to dung dch c l l ng Ca(OH)2, suy ra mu ban u l kim loi Ca. L no to dung dch trong sut l NaOH, suy ra mu ban u l Na.

CO2 + Ca(OH)2 CaCO3 + H2O CO2 + 2NaOH Na2CO3 + H2O

Cho dung dch NaOH vo hai mu cn li, mu no tan trong NaOH l Al, mu cn li l Mg.

2Al + 2NaOH + 2H2O 2NaAlO2 (dd) + 3H2

Bi 3: Ba, Mg, Fe, Ag, Al (ch dng H2SO4) Ly mt t ha cht lm thuc th: Cho 5 mu thuc th vo 5 ng nghim cha dung dch H2SO4 long. ng nghim no

khng c bt kh thot ra l Ag. ng no c kh thot ra v c kt ta trng l Ba. Cc ng nghim cn li to dung dch trong sut v c bt kh thot ra (kh H2) gm Mg, Fe v Al.

Cc phng trnh phn ng xy ra: Khi cho Ba vo axit H2SO4 th u tin xy ra phn ng:

Ba + H2O Ba(OH)2 + H2 Tip theo:

Ba + H2SO4 BaSO4 (trng) + H2 Mg + H2SO4 MgSO4 + H2 Fe + H2SO4 FeSO4 + H2 2Al + 3H2SO4 Al2(SO4)3 + 3H2

Tip tc, trong ng nghim nhn bit c Ba, lc b kt ta BaSO4, cn li l dung dch Ba(OH)2. Cho 3 kim loi cn li gm Mg, Fe v Al vo 3 ng nghim cha dung dch Ba(OH)2, ng nghim no c kim loi tan ng thi c kh thot ra, l l ng Al.

2Al + Ba(OH)2 + 2H2O Ba(AlO2)2 + 3H2 ng thi cho dung dch Ba(OH)2 vo hai l dung dch MgSO4, FeSO4. ng nghim no

c kt ta trng ri bin thnh mu nu l FeSO4(do kt ta trng ca BaSO4 ha ln vi kt ta Fe(OH)2 mu xanh l a) ng vi kim loi Fe. ng nghim cn li l MgSO4 ng vi kim loi Mg.

Phng trnh phn ng: Ba(OH)2 + FeSO4 BaSO4 (trng) + Fe(OH)2 Ba(OH)2 + MgSO4 BaSO4 (trng) + Mg(OH)2

Bi 4: Mg, Zn, Fe, Ba - Ly 4 ng nghim, mi ng cha mt t dung dch H2SO4, cho ln lt tng kim loi

vo cc kim loi trn, ng no c bt kh bay ra v xut hin kt ta l Ba. Cc phng trnh phn ng xy ra: Khi cho Ba vo axit H2SO4 th u tin xy ra phn ng:


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Ba + H2O Ba(OH)2 + H2 Tip theo:

Ba + H2SO4 BaSO4 (trng) + H2 Mg + H2SO4 MgSO4 + H2 Fe + H2SO4 FeSO4 + H2 Zn + 3H2SO4 ZnSO4 + H2

Tip tc, trong ng nghim nhn bit c Ba, lc b kt ta BaSO4, cn li l dung dch Ba(OH)2. Cho 3 kim loi cn li gm Mg, Fe v Zn vo 3 ng nghim cha dung dch Ba(OH)2, ng nghim no phn ng v c kh thot ra l ng nghim c cha kim loi Zn.

Zn + Ba(OH)2 BaZnO2 + H2 Cho tip Ba(OH)2 vo 2 ng nghim cha cc dung dch MgSO4, FeSO4 c trn.

ng nghim c kt ta trng v khng i mu l ng MgSO4, t suy ra kim loi tng ng l Mg. ng nghim cn li c kt ta mu trng sau chuyn sang mu nu l FeSO4, t suy ra kim loi cn li l Fe.

FeSO4 + Ba(OH)2 Fe(OH)2 + BaSO4 MgSO4 + Ba(OH)2 Mg(OH)2 + BaSO4

2.1.1.2. Nhn bit phi kim: (kh dng n cht) a. Nhng phn ng c trng:

Cht cn nhn bit Thuc th Hin tng Phng trnh phn ng

F2 Kh mu lc nht

Nc Br2 Nc Br2 nht mu

5Cl2 + Br2 + 6H2O10HCl + 2HBrO3 Cl2

Dung dch KI + h tinh bt

T khng mu mu xanh

Cl2 + 2KI 2KCl + I2 H tinh bt + 2I Mu xanh

Cht lng mu nu

Nc clo Nc Br2 nht mu

5Cl2 + Br2 + 6H2O10HCl + 2HBrO3

Br2

Kh SO2 Nc Br2 nht mu

SO2 + Br2 + 2H2O H2SO4 + 2HBr

un nng Tinh th thng hoa (hi mu tm)

I2

H tinh bt T khng mu mu xanh

Que m tn

Bng chy O2

Cu (mu ),to CuO (mu en) 2Cu + O2 ot 2CuO H2 CuO (mu

en), to Cu (mu ) H2 + CuO ot Cu + H2O

b. Mt s bi tp tiu biu: Bi 1: Nhn bit cht kh: c cc l ng kh ring bit sau


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a- O2, Cl2, O3 b- N2, H2, Cl2, F2.

Bi 2: Nhn bit cc kh sau cha trong cc l ring bit bng phng php ha hc: O2, O3, N2, Cl2. Bi gii

Bi 1: a. Quan st mu ca cc kh ta thy mt trong nhng l kh c mu vng lc, l kh Cl2. Dng giy tm h tinh bt v dung dch KI nhn bit kh O3. O3 + 2KI + H2O O2 + I2 + 2KOH. L cn li ng O2. b. Quan st mu cc l kh ta thy, c mt l kh mu vng lc l Cl2. Mt l kh mu lc nht l l kh F2. Hai l kh cn li dng dung dch Ca(OH)2 nhn bit, l kh no lm dung dch Ca(OH)2 c th l l kh CO2. L cn li l H2.

Bi 2: Quan st mu cc l kh ta thy l no c mu vng lc l kh Cl2. Dng giy tm h tinh bt v dung dch KI nhn bit kh O3. O3 + 2KI + H2O O2 + I2 + 2KOH. Hai l kh cn li a que dim cn m vo, l no lm que dim chy mnh l l ng kh O2. L cn li l N2.

2.1.2. Hp cht 2.1.2.1. Nguyn tc

- nhn bit mt ion trong dung dch, ngi ta thm vo dugn dch mt thuc th to vi ion mt sn phm c trng nh: mt cht kt ta, mt hp cht c mu hoc cht kh kh tan si bt, hay bay khi dung dch.

- nhn bit mt kh, ngi ta c th da vo tnh cht vt l hoc tnh cht ha hc c trng ca n.

Mt s hin tng nhn bit mt s ion (cation v anion): Cht th

(thuc th) Thuc th (cht th) Hin tng Phn ng

24SO

Kt ta trng 2Ba + + 24SO BaSO4 2Ba + 23CO

Kt ta trng 2 23 3Ba SO BaSO+ + 24SO

Kt ta trng Ca2+ + SO42- CaSO4 2Ca + 23CO

Kt ta trng 2 23 3Ba CO BaCO+ + OH Kt ta xanh 2 2( )Cu OH Cu OH+ + 2Cu + 2

3SO

Kt ta trng 2 23 3Cu SO CuSO+ + OH Kt ta trng 2 2( )Mg OH Mg OH+ + 2Mg + 2

3CO

Kt ta trng 2 23 3Mg CO MgCO+ + OH Kt ta trng xanh 2 2( )Fe OH Fe OH+ + 2Fe + 2

3CO

Kt ta trng 2 23 3Fe CO FeCO+ + OH Kt ta nu 3 3( )Fe OH Fe OH+ + 3Fe + 3

4PO

Kt ta trng 3 34 4Fe PO FePO+ +


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OH Kt ta en Ag OH AgOH+ + Ag +

Cl Kt ta trng Ag Cl AgCl+ + Mn2+ OH Kt ta trng 2 2( )Mn OH Mn OH+ +

3

2

2

3

AlZnBeCr

+

+

+

+

To phc tan trong kim d

4

4

4

4

[ ( ) ][ ( ) ][ ( ) ][ ( ) ]

Na Al OHNa Zn OHNa Be OHNa Cr OH

2.1.2.2. Nhn bit a. Oxit baz:

Dng: Hn ch thuc th Bi 1. Ch dng HCl v H2O. Hy nhn bit cc cht sau y ng ring bit trong cc l

mt nhn: BaO, MgO, MnO2, Al2O3, FeO, Fe2O3. Hng dn

- Xem nhng oxit trn thuc loi oxit no (tan hay khng tan). - Cc oxit c to phc c hay khng. - Sn phm sau khi nhn bit c cht c th nhn bit c cc cht khc khng. - Cc cht s cho nhng du hiu g khi tc dng vi cht .(kt ta, kh thot ra, to

phc). Tr li

- Ly mi cht mt t lm mu th. - Cho nc vo tt c cc mu th, mu no tan th l BaO.

BaO + H2O Ba(OH)2 - Cho HCl vo cc mu th cn li, mu no c kh xut hin th l MnO2.

MnO2 + 4HCl MnCl3 + 12

Cl2 + 2H2O Fe2O3 + 6HCl 2FeCl3 + 3H2O FeO + 2HCl FeCl2 + H2O Al2O3 + 6HCl 2AlCl3 + 3H2O

- Dung dung dch Ba(OH)2 va nhn bit c trn cho vo ln lt cc mu th cn li:

+ Mu no c kt ta mu nu l FeCl3 Fe2O3 2FeCl3 + 3Ba(OH)2 2Fe(OH)3 + 3BaCl2

+ Mu no kt ta mu trng xanh l FeCl2 FeO FeCl2 + Ba(OH)2 Fe(OH)2 + BaCl2

+ Mu no c kt ta trng nhng tan trong Ba(OH)2 d l AlCl3 Al2O3 2AlCl3 + 3Ba(OH)2 2Al(OH)3 + 3BaCl2 Al(OH)3 + Ba(OH)2 Ba[Al(OH)4]2

Bi 2. Ch dng mt ha cht hy nhn bit cc l dng oxit mt nhn sau: Na2O, Al2O3, Fe2O3, MgO

Dng: Khng hn ch thuc th Bi 1. C 4 l ng 4 oxit dng bt b mt nhn sau: CuO, Al2O3, MgO, Fe2O3

Hng dn - Nhng oxit u dng bt, c tan trong nc khng.


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- Phi ha tan hay khng ha tan trc khi nhn bit. - Xc nh ng thuc th nhn bit dung dch sau khi ha tan thng qua dng mu kt

ta. Suy ra oxit ban u. Tr li: - Ly mi th mt t lm mu th - Ha tan cc mu th trn bng HCl, mu no khng tan trong HCl l CuO.

Al2O3 + 6HCl 2AlCl3 + 3H2O Fe2O3 + 6HCl 2FeCl3 + 3H2O MgO + 2HCl MgCl2 + H2O

- Dng thuc th NaOH nhn bit cc oxit thng qua dung dch sau khi ha tan bng HCl.

+ Mu no c kt ta mu nu l FeCl3 Fe2O3 FeCl3 + 3NaOH Fe(OH)3 + 3NaCl

+ Mu no c kt ta trng l MgCl2 MgO MgCl2 + 2NaOH Mg(OH)2 + 2NaCl + Mu no cho kt ta trng nhng tan ra trong NaOH d th l AlCl3 . Al2O3

AlCl3 + 3NaOH Al(OH)3 + 3NaCl Al(OH)3 + NaOHd Na[ ]4( )Al OH

Bi 2. C 4 oxit ng ring bit sau: FeO, MgO, MnO2, Cr2O3, CaO, Na2O. Hy nhn bit nhng oxit trn bng phng php ha hc.

b. Oxit axit: Dng: Khng hn ch thuc th:

Bi 1. C bn bnh ng bn kh sau: CO2, SO3, SO2, NO2. Hng dn - Xem cc kh trn dng no (oxit axit hay cn dng khc). - Cc oxit trn c ha tan vo nc khng. - Cc oxit trn c th to c axit khng. - Kh nng nhn bit tng oxit c d dng khng. - Chn thuc th thch hp nhn bit cc oxit . Tr li: - Ly mi kh mt t lm mu th. - Dn cc kh trn qua nc to thnh dung dch axit.

CO2 + H2O H2CO3 SO3 + H2O H2SO4 SO2 + H2O H2SO3 NO2 + H2O HNO3

- Dng thuc th Ba(OH)2 cho vo cc dung dch trn, dung dch no khng cho kt ta th l HNO3 NO2

H2SO4 + Ba(OH)2 BaSO4 + 2H2O H2SO3 + Ba(OH)2 BaSO3 + 2H2O H2CO3 + Ba(OH)2 BaCO3 + 2H2O

- Dng thuc th Mg(OH)2 cho vo dung dch ban u nu dung dch no khng cho kt ta l H2SO4 SO3

H2SO3 + Mg(OH)2 MgSO3 + 2H2O H2CO3 + Mg(OH)2 MgCO3 + 2H2O


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- Ly H2SO4 va nhn bit c trn cho vo hai mu kt ta trn mu no c kh thot ra th l MgCO3 CO2

H2SO4 + MgCO3 MgSO4 + H2O + CO2 - Cn li l MgSO3 SO2.

Bi 2. Hy nhn bit cc oxit sau bng phng php ha hc: CO, SO3, P2O5, N2O5.

c. Axit Dng: Khng hn ch thuc th

Bi 1. Hy phn bit cc dung dch axit b mt nhn sau: HCl, H2SO4, HNO3, H2CO3. Hng dn: - Cc axit trn c phi u dng dung dch khng. - Xc nh thuc th cho phn ng vi dung dch axit cho nhng mu sc hoc kt ta hoc c kh xut hin khng. Tr li: - Ly mi cht mt t lm mu th. - Dng thuc th Fe(OH)2 cho vo tng mu th, mu no cho kt t mu trng l H2CO3.

H2CO3 + Fe(OH)2 FeCO3 + 2H2O - Dng thuc th Ba(OH)2 cho vo mu cn li, mu no cho kt t mu trng l H2SO4.

H2SO4 + Ba(OH)2 BaSO4 + 2H2O - Dng thuc th AgNO3 cho vo 2 mu cn li, mu no c kt ta trng l HCl.

HCl + AgNO3 AgCl + HNO3 - Cn li l HNO3. VD2: Trong phng th nghim c cc l ng dung dch axit b mt nhn: H2S, HCl, HNO3, H2SO3.

d. Mui Dng:Khng dng ha cht.

Bi 1. C 3 dung dch mui Ba(NO3)2, K2SO4, Ba(HCO3)2. Hy nhn bit ba mui trn. Hng dn: - Xem cc mui trn c cc gc axit nh th no. - Cc cation c kh nng to kt ta vi cc gc axit trong cc mui trn khng. - Chn cp mui thch hp.

Tr li: - Ly mi dung dch mui mt t lm mu th. Ba(NO3)2 K2SO4 NaHCO3 Ba(NO3)2 Khng phn ng Kt ta Si bt kh K2SO4 Kt ta Khng phn ng Si bt kh

NaHCO3 Si bt kh Si bt kh Khng phn ng

Bi 2. C 3 dung dch mui Ca(HSO3)2, Na2CO3, MgCl2, AgNO3. Hy nhn bit ba mui trn.

Dng: Hn ch thuc th. Bi 1. Ch dng mt loi thuc th, hy nhn bit cc dung dch mui sau: (NH4)2SO4,

FeCl3, MgCl2, Cr(NO3)3. Tr li:


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- Ly mi th mt t lm mu th. - Dng thuc th NaOH cho ln lt vo cc mu trn; + Mu no c kh thot ra th l (NH4)2SO4.

(NH4)2SO4 + 2NaOH Na2SO4 + 2NH3 + 2H2O + Mu no c kt ta nu l FeCl3.

FeCl3 + NaOH NaCl + Fe(OH)3 + Mu no c kt ta trng l MgCl2.

MgCl2 + NaOH NaCl + Mg(OH)2 + Mu no cho kt ta mu xanh ri tan ra trong NaOH d th l Cr(NO3)3.

Cr(NO3)3 + NaOH Cr(OH)3 + NaNO3 Bi 2. Ch dng mt loi thuc th, hy nhn bit cc dung dch mui sau: NH4Cl, FeCl2,

Al2(SO4)3, AgNO3. Bi 3. C 6 l mt nhn ng 6 dung dch: K2CO3, (NH4)2SO4, MgSO4, Al2(SO4)3,

FeSO4, Fe2(SO4)3. Ch dng mt thuc th nhn bit cc cht trn.

Dng: Khng hn ch thuc th. Bi 1. C cc l ng cc dung dch mui sau: K2SO4, NaHCO3, Ba(NO3)2, MgCl2, KI.

Hy nhn bit tng mui trn bng phng php ha hc. Tr li:

- Ly mi th mt t lm mu th. - Dng thuc th NaOH cho vo tng mu th trn, mu no c kt ta trng th l MgCl2.

MgCl2 + NaOH 2NaCl + Mg(OH)2 - Dng thuc th AgNO3 cho vo 3 mu cn li, mu no cho kt ta mu vn th l KI.

KI + AgNO3 AgI + KNO3 - Dng thuc th Na2CO3 cho vo mu cn li mu no cho kt ta trng th l Ba(NO3)2.

Ba(NO3)2 + Na2CO3 BaSO4 + 2NaNO3 - Dng thuc th Ba(NO3)2 nhn bit K2SO4 c kt ta mu trng.

Ba(NO3)2 + K2SO4 BaSO4 + KNO3 - Cn li l NaHCO3.

Bi 2. C cc l ng cc dung dch mui sau: K2SO4, Na2CO3, BaCl2, Al2(SO4)3, Mg(NO3)2. Hy nhn bit tng mui trn bng phng php ha hc.

e. Tng hp. Dng: Hn ch thuc th.

Bi 1. Ch s dng qu tm, hy nhn bit cc l ng cc dung dch sau: NaOH, MgCl2, Cr(NO3)3, FeCl3, H2SO4, Ba(NO3)2, KNO3.

Tr li: - Ly mi th mt t lm mu th. - Dng qu tm cho vo tng mu, th mu no lm qu tm ha xanh l NaOH, mu no lm qu tm ha l H2SO4. - Ly dung dch NaOH va nhn bit c cho vo ln lt tng mu. + Mu no c kt ta trng th l MgCl2.

2NaOH + MgCl2 2NaCl + Mg(OH)2 + Mu no c kt ta nu l FeCl3.

FeCl3 + 3NaOH 3NaCl + Fe(OH)3


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+ Mu no c kt ta xanh nhng tan ra trong NaOH d th l Cr(NO3)3. 3NaOH + Cr(NO3)3 3NaNO3 + Cr(OH)3 NaOH + Cr(OH)3 ( )4Na Cr OH

- Ly dung dch H2SO4 va nhn bit c trn cho vo cc mu cn li, mu no cho kt ta trng th l Ba(NO3)2.

Ba(NO3)2 + H2SO4 BaSO4 + 2HNO3 - Cht cn li l KNO3. Dng : Khng dng thuc th.

Bi 1. C bn l mt nhn c nh s t 1 n 4 cha cc dugn dch sau : KI, AgNO3, HCl, Na2CO3.Xc nh mi dung dch trn. Tr li:

KI AgNO3 HCl Na2CO3 KI Khng phn ng vng Tan Tan AgNO3 vng Khng phn ng trng Tan HCl Tan trng Khng phn ng Si bt kh Na2CO3 Tan Tan Si bt kh Khng phn ng

Dng: Khng hn ch thuc th. Bi 1. C 6 l mt nhn : BaCl2, K2CO3, Ca(OH)2, H2SO4(long), HCl, NH4HSO4. Hy tm

cch nhn bit cc dung dch trn. Tr li : - Ly mi th mt t lm mu th. - Ly qu tm cho vo tng mu, mu no lm qu tm ha xanh l Ca(OH)2 ; qu tm ha

l H2SO4 v HCl Cho thuc th Ba(OH)2 vo hai xit va nhn bit c, mu no cho kt ta trng th l

H2SO4. Ba(OH)2 + H2SO4 BaSO4 + 2H2O

Cn li l HCl. - Ly HCl va nhn bit cho vo cc mu cn li mu na c kh xut hin th l

K2CO3. K2CO3 + 2HCl 2KCl + H2O + CO2

- Ly thuc th MgSO4cho vo cc mu cn li mu no c kt ta trng l BaCl2. BaCl2 + MgSO4 MgCl2 + BaSO4

- Cn li l NH4HSO4.

2.2. Hu c 2.2.1. Hidrocacbon 2.2.2.1. Kin thc trng tm - Nm vng nhng tnh cht vt l cng nh nhng tnh cht ha hc - Cn nh nhng phn ng c trng ca tng loi hidrocacbon. c bit l nhng hin tng xy ra khi thc hin cc phn ng c trng ny.

Cht cn nhn bit Thuc th Hin tng Ankan Cl2 Sn phm sau phn ng

lm hng giy qu tm


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m Anken Nc brom

( mu da cam ) Mt mu dung dch brom

Dung dch thuc tm KMnO4

Mt mu dung dch thuc tm

Ankadien ( CnH2n-2 n>= 3)

Nc brom Mt mu dung dch brom

Ankin Nc brom Mt mu dung dch brom Dung dch thuc tm


Dung dch AgNO3 trong NH3

Cho kt ta mu vng nht

Dung dch CuCl trong NH3

Cho kt ta mu

Aren Brom lng ( bt Fe ) Mt mu dung dch brom Toluen Dung dch thuc tm

KMnO4 v un nng Mt mu dung dch thuc

tm Stiren Dung dch thuc tm

KMnO4 nhit thng


C hai hnh thc nhn bit hidrocacbon: - Nhn bit bnh thng - Nhn bit c gii hn ha cht

2.2.2.2. Nhn bit * Nhn bit bnh thng: 1. Nhn bit n- hexan, n- heptan, hexen-1, hexin-1, benzen, toluen v stiren cha trong cc bnh mt nhn 2. Nhn bit n-butan, buten-1, butadien 1-3 v butin-1 Hng dn gii: 1. - Cho AgNO3 / NH3 vo nhn bit c hexin-1 - Cho nc brom vo nhn bit c hexen-1, stiren. Sau em t ri cho i qua Ca(OH)2 cht no cho kt ta nhiu l striren t l hexen-1 - Cc cht cn li cho tc dng vi dung dch KMnO4 nhn bit c toluen - Cc cht cn li cho tc dng vi dung dch HNO3 c + H2SO4 nhn bit c benzen - Hai cht cn li em t ri cho i qua Ca(OH)2 cht no cho kt ta nhiu n-heptan l t l n- hexan

2. - Cho AgNO3 / NH3 vo nhn bit c butin-1 - Ly cng mt th tch 3 kh cho qua cng mt lng nc brom, mu no khng nht mu l butan, nht mu t l buten-1, nht mu nhiu l butadien 1-3

* Nhn bit c gii hn ha cht (T gii) 1. Hy nhn bit butan, buten-1, butin-2 v vinylaxetilen m ch dng mt ha cht duy nht 2. Nhn bit metan, etilen, axetilen, vinylaxetilen, benzen v stiren bng mt ha cht duy nht


12

* Nhn bit c gii hn ha cht (T gii) 1. - Ly cng mt th tch 4 kh cho qua cng mt lng nc brom, mu no khng nht mu l butan, nht mu t nht l buten-1, nht mu t l butin-2, nht mu nhiu l vinylaxetilen 2. - Da vo trng thi vt l ta ta nhn bit c benzen v stiren. Sau cho nc brom th stiren s lm mt mu nc brom, benzen th khng - Ly cng mt th tch 4 kh cho qua cng mt lng nc brom, mu no khng nht mu l metan, nht mu t nht l etilen, nht mu t l axetilen, nht mu nhiu l vinylaxetilen

2.2.2. Dn xut 2.2.2.1. Nguyn tc

+ Phn bit ru cng dy ng ng c PTL khc nhau: Ly nhng khi lng bng nhau cc mu th cho tc dng vi Na d ri da vo th tch kh H2 thot ra nhn bit: Vi cng khi lng cc mu th, mu no c PTL cng nh s to ra VH2 cng ln.

+ Phn bit ancol bc khc nhau: Dng thuc th Lucas ( HCl c + ZnCl2 khan) Ancol bc 3: Phn ng nhanh nht, lp clorua to thnh khng tan, ni ln: dung dch

b phn lp. Ancol bc 2: Phn ng chm hn, mt lng nh clorua to thnh lm cho dung dch

c. Ancol bc 1: iu kin thng trong thi gian ngn, vn cha xy ra phn ng,

dung dch trong sut v khng phn lp. + i vi cc hp cht c nhm chc khc th s dng cc phn ng c trng nhn

bit chng.

STT

Tn Hp cht

Cng thc

Tnh tan Phn ng ha hc c trng

1 Phenol Ar-OH

- Tan t trog nc lnh, tan v hn 660C - Tan tt trong etanol, ete, axeton..

C6H5OH + Na C6H5ONa + H2 C6H5OH + NaOH C6H5ONa + H2O

O H

+ 3 Br 2

O HB rB r

B r

+ 3 H B r

2 Anehit - Xeton

R-CH=O R C R

O

HCHO, CH3CHO tan tt tron nc v dung mi hu c

- Tc dng vi brom, KMnO4 R-CH=O + Br2 + H2O RCOOH + 2HBr - Tc dng vi AgNO3/NH3 R-CH=O + 2[Ag(NH3)2]OH R-COONH4 + 2 Ag + 3 NH3 + H2O

3 Axit cacboxyli

R-COOH C1-3 tan tt trong nc

- Tnh axit - Phn ng este ha


13

2.2.2.2. Nhn bit Nhn bit khng hn ch thuc th.

Bi 1. Nhn bit cc mu th trong tng dy ho cht sau y: Phenol, etanol, glixrol, benzen. Hng dn

Nhn bit cc mu th cho da vo hin tng ghi nhn trong bng sau:

Cc phn ng :

O H

+ 3 Br 2

O HB rB r

B r

+ 3 H B r

c

4 Este R-COO-R t tan trong nc

- Phn ng thy phn - Phn ng kh bi LiAlH4 R-COO-R 04 ,tLiAlH R-CH2-OH + R-OH

5 Cacbohirat

Cn(H2O)m D tan trong nc

- Tc dng vi [Ag(NH3)2]OH: Glucoz, Mantoz - Tc dng vi Cu(OH)2: Glucoz, Fructoz, Saccaroz, Mantoz - Thy phn: Saccaroz, Mantoz, Tinh bt, Xenluloz

6 Amin R-NH2 R2-NH R3-N

CH3NH2, (CH3)2NH, (CH3)3N, C2H5NH2 tan tt trong nc

- To mui amoni: R-NH2 + HCl R-NH3+ + Cl-

- C2H5-NH2 + HONO C2H5OH + N2 + H2O C6H5-NH2+HONO +HCl C

050 C6H5N2+Cl- + 2 H2O

N H 2

+ 3 Br 2

N H 2B rB r

B r

+ 3 H B r

7 Aminoaxit

H2N-R-COOH

D tan trong nc

- C tnh cht ca nhm NH2 v nhm -COOH

Thuc th phenol etanol glixerol benzen Br2 Kt ta trng - - -

Cu(OH)2 - - Dd xanh lam - Na Si bt kh Si bt kh Si bt kh -

CH2CHCH2

OHOHOH

+CH2CHCH2

OHOHOH

+Cu(OH)2CH2CH

CH2

OHO

O

CH2CH

CH2

OHO

OCu-

H

H

+ OH2


14

C2H5OH + Na C2H5ONa + H2 Bi 2. Nhn bit cc mu th trong tng dy ha cht sau y: Propan-1-ol, propan-2-ol, ietylete, glixerol, ancol alylic.

Hng dn - Cho cc mu th phn ng vi dung dch Br2, mu lm phai mu dung dch Br2 l ancol alylic. Phng trnh phn ng: CH2=CH-CH2-OH + Br2 CH2Br-CHBr-CH2-OH -Trong cc mu cn li, mu no ha tan Cu(OH)2 v to thnh dung dch xanh lam trng l glixerol. Phng trnh phn ng:

CH2CHCH2

OHOHOH

+CH2CHCH2

OHOHOH

+Cu(OH)2CH2CH

CH2

OHO

O

CH2CH

CH2

OHO

OCu-

H

H

+ OH2

- Cho 3 mu cn li tc dng vi Na, mu no khng phn ng ( khng c hin tng si bt kh ) l ietylete: C2H5-O-C2H5.

- em oxi ha 2 mu cn li sau cng bng CuO/t0 , mu th no to sn phm c th cho c phn ng trng gng l ancol bc nht ( propan-1-ol).

Phng trnh phn ng: C2H5-CH2-OH + CuO C2H5-CHO + Cu + H2O C2H5-CHO + AgNO3 + 3NH3 +H2O C2H5-COONH4 + 2NH4NO3 + 2Ag

- Cn li sau cng l propan- 2-ol. CH3-CHOH-CH3 +CuO CH3-CO-CH3 + Cu + H2O

( Khng cho phn ng trng gng ) Bi 3. C 4 ng nghim cha dn nhn cc cht ring r sau: Ancol etylic, axit axetic, anehit axetic, phenol lng. Bng phng php ha hc hy nhn bit tng cht . Vit phng trnh phn ng .

Hng dn - Cho tc dng vi dung dch Br2 , cht no c kt ta trng xut hin l phenol. Phng trng phn ng

O H

+ 3 Br 2

O HB rB r

B r

+ 3 H B r

- Cho Phn ng trng gng vi 3 cht cn li, cht no c kt ta trng bc l CH3CHO. Phng trnh phn ng

CH3-CHO + 2AgNO3 + 3NH3 +H2O CH3-COONH4 + 2NH4NO3 + 2Ag - Cho tc dng vi CaCO3, cht no c bt kh thot ra l CH3COOH. Phng trnh phn ng - Cn li l C2H5OH.

Bi 4. Nhn bit cc dung dch sau: ng glucoz, ng fructoz, ng saccaroz. Hng dn

Cho tc dng vi dung dch AgNO3 trong amoniac: - Cht no khng tham gia phn ng trng gng l saccaroz. - Cht no c phn ng trng gng l glucoz.


15

C6H12O6 + [Ag(NH3)2]OH C5H11O5-COONH4 + 2 Ag + 3 NH3 + 2H2O

Ch : - trong mi trng baz ( dung dch AgNO3 trong amoniac), mt phn fructoz chuyn

ha thnh glucoz nn cng gy ra phn ng trng gng, cng to ra Cu2O khi tc dung vi Cu(OH)2

- Trong phng th nghim ngi ta dng thuc th rezosin trong mi trng axit nhn bit fructoz.

Bi 5. C hn hp 3 ng phn CH3CH2COOH, CH3-COOCH3, CH3-CHOH-CHO. Hy nhn bit tng ng phn trong hn hp bng phng php ha hc.

Hng dn - Cho CaCO3 vo hn hp, c kh thot ra chng t c axt: CH3CH2COOH + CaCO3 (CH3CH2COO)2Ca + CO2 + H2O - Cho vi git dung dch AgNO3 trong amoniac vo hn hp, c phn ng trng gng

chng t c anehit.

CH3-CHOH-CHO + 2[Ag(NH3)2]OH CH3-CHOH-COONH4 + 2NH4NO3 + 2Ag Bi 6. Hy dng cc phng php ha hc nhn bit cc ha cht HCOOH, CH3CH2CHO, CH3COOH, CH3-COOCH3.

Hng dn

HCOOH

CH3CH2CHO

Cho c 4 cht tc dng vi Na2CO3 cht no c kh thot ra l HCOOH v CH3COOH: Phng trnh phn ng:

HCOOH + Na2CO3 2 HCOONa + CO2 + H2O CH3COOH + Na2CO3 2CH3COONa + CO2 + H2O

Cho hai cht tc dng vi dung dch AgNO3 trong amoniac, cht no c phn ng trng gng l HCOOH cn li l CH3COOH.

Phng trnh phn ng HCOOH + 2AgNO3 + 4NH3 +H2O (NH4)2CO3+ 2NH4NO3 + 2Ag

- Cng cho hai cht CH3CH2CHO v CH3-COOCH3 ln lt tc dng vi dung dch AgNO3 trong amoniac, cht no c phn ng trng gng l CH3CH2CHO cn li l CH3COOCH3.

Phng trnh phn ng C2H5-CHO + 2AgNO3 + 4NH3 +H2O C2H5-COONH4 + 2NH4NO3 + 2Ag

Bi 7. Nhn bit cc mu th trong dy ha cht sau y: CH3COOH, CH2=CH-COOH, C2H5-OH, C2H4(OH)2, CH3-CHO

Na2CO3 HCOOH CH3CH2CHO CH3COOH

CH3-COOCH3

HCOOH CH3COOH

CH3CH2CHO CH3-COOCH3

AgNO3/NH33

AgNO3/NH3


16

Hng dn

- Cho tng lng nh mu vo dung dch AgNO3/NH3 un nng, mu no cho kt ta Ag l CH3-CHO.

Phng trnh phn ng: CH3-CHO + 2AgNO3 + 3NH3 +H2O CH3-COONH4 + 2NH4NO3 + 2Ag

( hoc m th no khng tc dng vi Na l CH3-CHO cng c) - Trong s cc mu cn li, mu no lm i mu giy qu tm m v phai mu dung dch

Br2 l CH2=CH-COOH. Phng trnh phn ng:

CH2=CH-COOH + Br2 CH2Br-CHBr-COOH - Mu ch lm i mu qu tm m l CH3COOH. - Cho dung dch Cu(OH)2 vo 2 mu sau cng, mu ha tan c Cu(OH)2 v to dung

dch xanh lam l etylenglicol. Phng trnh phn ng:

CH2CHCH2

OHOHOH

+CH2CHCH2

OHOHOH

+Cu(OH)2CH2CH

CH2

OHO

O

CH2CH

CH2

OHO

OCu-

H

H

+ OH2

Bi 8. Nhn bit cc mu th trong tng dy ha cht sau y: Propan-1-ol, Propanal, axit fomic, axit Propanoic.

Hng dn - Trong 4 mu th cho, mu no l qu tm m ha , ng thi cho phn ng trng

gng l axit HCOOH: HCOOH + 2AgNO3 + 4NH3 +H2O (NH4)2CO3+ 2NH4NO3 + 2Ag

- Mu khng lm qu tm m i mu nhng c th cho phn ng trng gng l propanal. C2H5-CHO + 2AgNO3 + 4NH3 +H2O C2H5-COONH4 + 2NH4NO3 + 2Ag

- Trong 2 mu cn li, mu no lm qu tm i mu l axit propanoic. - Mu sau cng cn li l Propan-1-ol.

Nhn bit bng mt thuc th. Bi 1. Nhn bit cc mu th trong tng dy ha cht sau y:

Etanol, etanal, axit etanoic, propantriol ( bng 1 thuc th duy nht) Hng dn

Cho tng lng nh cc mu th tc dng vi dd Cu(OH)2: - Nu to thnh dung dch mu xanh nht l axit etanoic:

CH3COOH + Cu(OH)2 (CH3COO)2Cu + 2H2O - Nu to thnh dung dch mu xanh lam trong sut l propantriol( glixerol).

CH2CHCH2

OHOHOH

+CH2CHCH2

OHOHOH

+Cu(OH)2CH2CH

CH2

OHO

O

CH2CH

CH2

OHO

OCu-

H

H

+ OH2

- Nu to thnh kt ta gch khi un nng l etanal


17

- Mu cn li sau cng l etanal. Bi 2. Nhn bit cc mu th trong tng dy ha cht sau y: CH3COOH, H2N-CH2-COOH, H2N-CH2-CH(NH2)-COOH.

Hng dn

Cho qu tm vo cc mu th: - Mu lm qu tm ha l: CH3COOH - Mu lm qu tm ha xanh l: H2N-CH2-CH(NH2)-COOH - Mu khng i mu qu tm l: H2N-CH2-COOH

3. Tch cht 3.1. Tch cht v c 3.1.1. C s l thuyt

Nm vng cc tnh cht ca cc n cht (kim loi v phi kim), nm vng cc iu kin phn ng ca tng loi cht Trn c s ra cc phng php phn bit, tch v tinh ch cc n cht mt cch d dng.

Mt s lu : - Dng cc p c hiu hay thuc th nhn bit tng cht hay tng nhm cht chung 1

p c hiu - Trong cc cht cho chung 1 p c hiu ta c th dng thm cc p khc (nu cho

php) - Nu cc cht u cho c du hiu cha th nhn bit r, th ta nn chuyn ha chng thnh 1 cht trung gian, ri li dng thuc th nhn bit chng => cht tng ng ban u.

- Mun iu ch kim loi kim v kim th ngi ta in phn nng chy mui clorua, khng dng mui sunfat (kh nng chy), mui Nitrat (d n).

- Ring Al c iu ch bng cch in phn nng chy Al2O3, khng in phn nng chy mui nhm v mui ny d b thng hoa.

- Mun lm kt ta hon ton ion Al3+ nn cho dung dch Al3+ tc dng vi dung dch NH3: Al3+ + 3NH4OH Al(OH)3 + 3NH4+

- Hai kim loi Fe v Al th ng vi cc axit HNO3 c ngui v H2SO4 c ngui. - Dung dch mui no to mi trng axit, baz hay trung tnh?

3.1.2. So snh tch v tinh ch Cho mt hn hp cht V: A + B + C +D Tch cht A, B, C, D ra khi hn hp V tc l tch ring tng cht mt, sau phi a

cc cht y v ng trng thi nguyn thu ca chng. Ngha l phi nm tht vng cc phng php iu ch (kim loi, phi kim, oxit, axit, baz, mui) c th a tr li cc cht A, B, C, D v ng trng thi ban u ca n.

Tinh ch A ngha l tm cch loi b ht B, C, D (c th xem chng ng vai tr l tp cht), sn phm cui cng ch cn li l A nguyn cht. Sau khi loi b B, C, D ta cn phi

CH3-CHO + Cu(OH)2 CH3-COOH + Cu2O + 2H2O t0

gch


18

a A v ng trng thi ban u ca n trong hn hp V. V d: nu A l kim loi trong hn hp V th sau khi tch c A ra di dng mui th phi t mui ny iu ch ra kim loi A. 3.1.3. Cc phung php tch v tinh ch

Phng php i tng - Ha tan trong axit

- Ha tan trong baz

- Ha tan trong nc

- in phn - Nhit phn - un nng - Chng ct phn on - Lm khan

- Kim loi, oxit baz, oxit lng tnh, mui khng tan trong nc nh CO32-, SO42-

- Oxit hidroxit ca kim loi lng tnh, oxit axit - Cc cht d tan trong nc

- Cc kim loi c tnh kh bt thng - Cc cht khng bn - Cc cht d bay hi, cht thng hoa - Cc cht c si khc nhau

- Cc cht ht m

3.1.4. Bi tp Bi 1. Thm mt t bt ng vo dung dch bc nitrat. Sau mt khong thi gian, ngi ta

thu c hn hp hai mui v hn hp hai kim loi. Hy nu cch tch ring tng kim loi ra khi hn hp trn.

Tm tt: AgNO3 Cu hn hp 2 mui

hn hp 2 kim loi. Tch ring tng kim loi? Cch 1. t nng hn hp kim loi trong oxi, c hn hp CuO v Ag. Ngm hn hp

ny trong dung dch H2SO4 long. c CuSO4 v Ag. Lc tch ring Ag v CuSO4. in phn dung dch CuSO4, thu c Cu trong catot.

Cch 2. Ngm hn hp hai kim loi trong dung dch AgNO3, c dung dch Cu(NO3)2 v kim loi Ag. Lc tch Ag. T dung dch Cu(NO3)2 iu ch Cu bng phng php in phn hoc qua bin i ha hc, nh dng Fe, Zn kh Cu2+ thnh Cu.

TCH TINH CH N CHT

Kim loi Phi kim

Ha tan

in phn

Nhit phn

un nng

Chng ct

Lm khan


19

Bi 2.C hn hp bt cc kim loi sau: Cu, Al, Fe, Ag. Hy dng cc phng php ho hc tch ring tng kim loi c trong hn hp trn. Tm tt: Tch ring tng kim loi trong hn hp Cu, Al, Fe, Ag? - Ngm hn hp cc kim loi trong dung dch H2SO4 long, c dung dch V cha 2 mui Al2(SO4)3, FeSO4, H2SO4 (d) v cht rn l hn hp Cu, Ag. - Ngm hn hp Cu, Ag trong dung dch AgNO3, thu c Ag v dung dch Cu(NO3)2 c ln mt lng AgNO3 d. Thm mt lng Cu d vo dung dch 2 mui. Nc lc l dung dch Cu(NO3)2. in phn dung dch ny, thu c Cu catot. - Ngm mt lng bt Al (d) vo dung dch V c hn hp rn l Fe v Al (d) v dung dch V2 l Al2(SO4)3. T dung dch V2 iu ch c Al theo s :

Al2(SO4)3 Al(OH)3 Al2O3 dp Al - Ngm cht rn gm Fe v Al (d) vo dung dch NaOH, thu c Fe.

Bi 3. X l 8,3g hn hp bt cc kim loi Fe v Al bng dung dch HCl va . Phn ng xong ngi ta thu c 8,4l kh hiro (136,50C, v 760 mmHg) v dung dch A. Hi dung dch A gm nhng cht no? Trnh by phng php tch ring tng kim loi c trong hn hp mui ca dung dch A.

Tr li: T cc d liu bi, cho thy dung dch A c 2 mui l AlCl3 v FeCl2, c th dng phng php sau: cho dung dch A tc dng vi lng d bt Al, phn ng xong, ta oc dung dch AlCl3 v cht rn l Fe c ln bt Al. Ngm cht rn trong dung dch NaOH c nng, d ta thu c cht rn l kimloi Fe. T dung dch AlCl3, iu ch c Al theo cch:

AlCl3 NaOH Al(OH)3 0t Al2O3 dpnc Al Bi 4. C hn hp Al, Fe v Mg. Hy trnh by phng php ha hc tch ring tng kim

loi ra khi hn hp. Tr li:

S tch cc kim loi: Al, Fe, Mg NaOH du NaAl(OH)4 2 2,CO H O+ + Al(OH)3 0t Al2O3 dpnc Al Fe, Mg HCl+ FeCl2, MgCl2 NaOH+ Fe(OH)2, Mg(OH)2

0t Fe2O3, MgO CO+ MgO, Fe 2 4 ,H SO dac nguoi Fe

MgSO4 2BaCl+ MgCl2 dpnc Mg Bi 5. Nu bc c ln tp cht l nhng kim loi km, thic v ch, bng cch no c th

loi b nhng tp cht? Tr li:

Ngm kim loi bc c ln tp cht trn vo dung dch AgNO3 d. Ion Ag+ s oxi ha nhng kim loi trong tp cht thnh nhng ion tng ng tan vo dung dch. Sau lc, ta c Ag tinh khit.

Bi 6. Trong phng th nghim bng phng php no c th tch c kh N2 v CO2 ra khi hn hp kh gm N2, O2, CO2, CO v hi nc?

Tr li:


20

Cho hn hp kh i qua ng ng photpho trng ( hp th O2): 4P + 5O2 2P2O5

Cho hn hp kh cn li (CO, CO2, N2 v hi nc) qua ng ng CuO un nng (CO phn ng):

CuO + CO 0t Cu + CO2 Kh cn li l N2, CO2 v hi nc qua bnh ng Ba(OH)2 d hp th CO2:

CO2 + Ba(OH)2 BaCO3 + H2O Kh cn li cho i qua H2SO4 c hp th nc, phn cn li l N2.

Kt ta BaCO3 cho tc dng vi H2SO4 thu hi CO2: BaCO3 + H2SO4 BaSO4 + CO2 + H2O

Bi 7. Tch hn hp N2, hi nc, SO2 v C2H4? Tr li:

- Dng Na2SO4 khan tch hi nc: Na2SO4 + 10H2O Na2SO4.10H2O

Na2SO4.10H2O 0t

H2O - Dng NaOH tch SO2:

SO2 2NaOH Na2SO3 HCl SO2 - Dng nc Br2 tch C2H4:

C2H4 2Br C2H4Br2 Zn C2H4 - Cn li l N2.

3.2. Tch Tinh ch hp cht 3.2.1. Phng php: 3.2.1.1. S dng phng php vt l - Phng php lc: Dng tch cht khng tan ra khi hn hp lng. - Phng php c cn: Dng tch tan rn ( khng ha hi khi nhit cao) ra khi dung dch hn hp lng. - Phng php ng c: Dng tch cc cht lng ra khi hn hp lng nu chng c nhit ng c ca chng cch bit nhau ln. - Phng php chit: Dng tch cc cht lng ra khi hn hp lng khng ng nht. - Phng php sc k: Dng tch hay phn tch cc hp cht kh, cht lng hay cht rn.

3.2.1.2. S dng phng php ha hc: Theo s sau:

+ X

AX+Y

XY

(A)

( B)

(A)( B)hh


21

Phn ng c chn phi tha mn 3 yu cu: - Ch tc dng ln 1 cht trong hn hp cn tch. - Sn phm to thnh c th tch d dng khi hn hp. - T sn phm phn ng to thnh c kh nng ti to c cht ban u.

3.2.2. Bi tp 1.Trnh by cch tch ri tng cht sau y ra khi hn hp cht rn sau: AlCl3,

FeCl3, BaCl2. S :

AlCl3FeCl3BaCl2

NaAlO2

Fe(OH)3 FeCl3

BaCl2

CO2, loc

+ HCl

Al(OH)3BaCl2

AlCl 3

BaCl2(r)NaOH du,loc

HCl

c can

c canAlCl3(r)

Cho hh tc dng vi NaOH d: AlCl3 + 4NaOH d NaAlO2 + 3NaCl + 2H2O FeCl3 + 3NaOH d Fe(OH)3 + 3NaCl

Lc ly Fe(OH)3, cho tc dng dd HCl v em i c cn thu c FeCl3 Fe(OH)3 + 3HCl FeCl3 + 3H2O

Dn kh CO2 qua dung dch cn li NaAlO2 + CO2 + H2O Al(OH)3 + NaHCO3

C cn dd thu c AlCl3(r), lc ly Al(OH)3 tc dng vi HCl v em dd thu c c cn: Al(OH)3 + 3HCl AlCl3 + 3H2O

2. Trnh by cch tch cc cht: Al2O3, Fe2O3, SiO2 ra khi hn hp bt ca chng. S :

Al2O3Fe2O3SiO2

dd H+loc SiO2

Al3+

Fe2+dd OH- du Fe(OH)3

dd AlO2-

Al(OH)3 Al2O3

Fe2O3O2

CO2 du t

Cho hn hp tc dng vi dd HCl, lc ly phn khng tan l SiO2 Al2O3 + 6HCl 2AlCl3 + 3H2O Fe2O3 + HCl 2FeCl3 + 3H2O

Cho hn hp 2 dung dch tc dng vi NaOH d, lc ly Fe(OH)3 nung trong khng kh s thu c Fe2O3

AlCl3 + 2NaOH d NaAlO2 + 3NaCl FeCl3 + NaOH d Fe(OH)3 + 3NaCl Fe(OH)3 + O2 Fe2O3(r) + H2O

Cho kh CO2 qua dung dch, ly Al(OH)3 nung s thu c Al2O3 NaAlO2 + CO2 + H2O Al(OH)3 + NaHCO3 2Al(OH)3

t

Al2O3(r) + 3H2O

3. Trnh by phng php ha hc tch ring tng kim loi ra khi hn hp: CuO, MgO, Al2O3.


22

CuOMgOAl2O3

Al(OH)3t

Al2O3 Al3+

Cu + MgO+ HCl

Cu

MgCl2 Mg

4. C hn hp NaCl, ZnCl2, CaCl2, NaSO4 dng rn. Trnh by cch tch ly NaSO4 dng tinh khit.

NaClZnCl2CaCl2NaSO4

Zn(OH)2

CaCl2NaCl

NaSO4

Na2CO3

NaOH locCaCO3

NaSO4NaCl NaSO4

Ha tan hh vo nc, mt phn mui CaSO4 kt ta. NaSO4 + CaCl2 2NaCl + CaSO4

Lc b CaSO4 , cho nc lc tc dng vi NaOH va : ZnCl2 + 2NaOH Zn(OH)2 + 2NaCl

Lc b Zn(OH)2 ly nc lc cho tc dng vi Na2CO3 va : CaCl2 + Na2CO3 CaCO3 + 2NaCl

Lc b CaCO3, c cn dung dch s thu c dung dch NaCl kt tinh, cho tc dng vi H2SO4 c, un nng cho bay hi ht HCl, s thu c NaSO4 dng tinh khit:

2NaCl + H2SO4 c Na2SO4 + 2HCl Nu H2SO4 d th trung ha bng mt lng NaOH va :

NaOH + H2SO4d Na2SO4 + 2H2O

3.3. Tch Hidrocacbon Dng 1: Tch cc cht ra khi hn hp cht hu c Bi 1. Hn hp kh gm: propan, etilen, axetilen. Hy tch tng cht ra khi hn hp.

Gii: 83HC

42

83

HCHC

2ddBr

Br CH2 CH2 Br Zn CH2 = CH2

22

42

83

HCHCHC

NHAgNO 33 /

AgC CAg onglHCl CH CH Phng trnh phn ng

CH CH + Ag2O 3NH

AgC CAg + H2O AgC CAg + 2 HCl CH CH + 2 AgCl CH2 = CH2 + Br2 Br CH2 CH2 Br


23

Br CH2 CH2 Br + Zn CH2 = CH2 + ZnBr2 Bi 2. Tch ri cc cht sau y ra khi hn hp:

a. metan, etilen, axetilen b. butin -1 , butin 2, butan

Gii

Phng trnh phn ng: 2 CHCCHCH 23 + Ag2O 3

NH 2 CH3 CH2 C CAg + H2O CH3 CH2 C CAg + HCl CHCCHCH 23 + AgCl

33 CHCCCH + 2 Br2 CH3 CBr2 CBr2 CH3 CH3 CBr2 CBr2 CH3 + 2 Zn 33 CHCCCH + 2 ZnBr2

Bi 3: Cho hn hpX gm bezen, phenol v anilin. Hy trnh by phng php ha hc tch ring tng cht ra dng nguyn cht.

Gii: - Cho X tc dng vi HCl:

C6H5NH2 + HCl C6H5NH3Cl (tan trong H2O) (Trong dd HCl phenol khng tan, C6H6 l cht lng khng tan) - Lc tch phn tan ri cho tc dng vi NaOH

C6H5NH3Cl + NaOH C6H5NH2 + H2O - Tch ly anilin khng tan trong H2O - Cho phn cn li (C6H5OH + C6H6) tc dng vi NaOH, lc tch c bezen. - Cht lng cn li cha C6H5ONa, cho kh CO2 d i qua:

C6H5OH + NaOH C6H5ONa + H2O C6H5ONa + CO2 + H2O C6H5OH + NaHCO3

Tch c phenol.

Dng 2: Tch tng cht ra khi hn hp cc cht hu c v v c Bi 1: C hn hp kh gm CO2, C2H2, C2H4, C2H6. Trnh by phng php ha hc thu c tng kh

Gii

Zn 33 CHCCCH

3223

33

23

CHCHCHCHCHCCCH

CHCCHCH

33 / NHddAgNO

CH3 CH2 C CAg HCl CHCCHCH 23

3223

33

CHCHCHCHCHCCCH

2ddBr

C4H6Br4

C4H10


24

Phng trnh phn ng: CO2 + Ca(OH)2 CaCO3 + H2O CaCO3

0t CaO + CO2

CH CH + 2 [Ag(NH3)2]+ AgC CAg + 2NH3 + 2 NH4+ AgC CAg + HCl 2 AgCl + CH CH CH2 = CH2 + Br2 Br CH2 CH2 Br Br CH2 CH2 Br + Zn CH2 = CH2 + ZnBr2

Bi 2: Tch ri cc cht sau ra khi hn hp: a. CH4, CO2, NH3 b. C2H6, CO2, SO2, HCl c. N2, NH3, CO2, SO2, C3H6

Bi 3: Tch ri cc cht ra khi hn hp a. CH4, C2H4, SO2, CO2 b. C4H10, C4H8, CO2

Bi 4: Cho hn hp kh gm C2H6, C2H4, C2H2, CO2 hy tch tng cht ra khi hn hp dng tinh khit v kh

Gii: Cho hn hp kh qua dung dch nc vi trong d CO2 b hp th CO2 + Ca(OH)2 CaCO3 + H2O

Kh C2H6, C2H4, C2H2 khng tc dng thot ra ngoi ta thu c hn hp 3 kh. - Lc tch CaCO3 cho tc dng vi H2SO4 long thu c CO2

CaCO3 + H2SO4 long CaSO4 + H2O + CO2 - Dn hn hp kh cn li qua dung dch AgNO3/NH3 d. C2H2 tc dng to kt ta mu vng. Hai kh C2H4, C2H6 khng tc dng thot ra ngoi. - Lc tch kt ta cho tc dng dung dch HCl thu c C2H2 c ln hi HCl. Cho dung dch NaOH ho th HCl thu c C2H2 tinh khit.

CH CH + Ag2O 3NH

AgC CAg + H2O AgC CAg + 2 HCl CH CH + 2 AgCl HCl + NaOH NaCl + H2O

- Hn hp kh cn li cho qua dung dch H2SO4 long, nng , C2H4 b hirat ha CH2 = CH2 + H2O longSOH 42 CH3 CH2 OH

duOHCa 2)(

CaCO3

62

42

22

HCHCHC

33 / NHAgNO

AgC CAg HCl CH CH

62

42

HCHC

2ddBr

C2H6

Br CH2 CH2 Br

62

42

22

2

HCHCHC

CO

CO2 CH2 = CH2 Zn


25

Cn li C2H6 ln C2H4 Ly ru thu c cho qua dung dch H2SO4 c, nng 1700C thu c CH2 = CH2

Kh C2H6 ln C2H4 cho qua dung dch Br2 (hoc KMnO4) cn li C2H6 CH2 = CH2 + Br2 Br CH2 CH2 Br Br CH2 CH2 Br + Zn CH2 = CH2 + ZnBr2

Cc kh sau khi tch ra khi hn hp cha kh, cho qua H2SO4 c (hoc P2O5) hp th ht hi nc cn li kh kh. H2SO4 c + nH2O H2SO4 .nH2O Hay P2O5 + 3H2O 2 H3PO4

3.4. Tch hn hp cc hp cht c nhm chc 3.4.1. Kin thc trng tm:

STT Tn Hp cht

Cng thc

Tnh tan Phn ng ha hc c trng

1 Ancol R-(OH)n Tan tt trong nc

R-OH + Na R-ONa + H2 R-ONa + H2O R-OH + NaOH - Glyxerol ha tan Cu(OH)2 - Tch nc: C2H5OH (C2H5)2O hoc C2H4

2 Phenol Ar-OH

- Tan t trog nc lnh, tan v hn 660C - Tan tt trong etanol, ete, axeton..

C6H5OH + Na C6H5ONa + H2 C6H5OH + NaOH C6H5ONa + H2O C6H5ONa + CO2 + H2O C6H5OH + NaHCO3

O H

+ 3 Br 2

O HB rB r

B r

+ 3 H B r

3 Anehit - Xeton

R-CH=O R C R

O

HCHO, CH3CHO tan tt tron nc v dung mi hu c

- Tc dng vi brom, KMnO4 R-CH=O + Br2 + H2O RCOOH + 2HBr - Tc dng vi AgNO3/NH3 R-CH=O + 2[Ag(NH3)2]OH R-COONH4 + 2 Ag + 3 NH3 + H2O

4 Axit

cacboxylic R-COOH C1-3 tan tt trong nc

- Tnh axit - Phn ng este ha

5 Este R-COO-R t tan trong - Phn ng thy phn

CH3 CH2 OH CH2 = CH2 + H2O H2SO4 c

1700C


26

nc - Phn ng kh bi LiAlH4 R-COO-R 04 ,tLiAlH R-CH2-OH + R-OH

6 Cacbohirat Cn(H2O)m D tan trong nc

- Tc dng vi [Ag(NH3)2]OH: Glucoz, Mantoz - Tc dng vi Cu(OH)2: Glucoz, Fructoz, Saccaroz, Mantoz - Thy phn: Saccaroz, Mantoz, Tinh bt, Xenluloz

7 Amin R-NH2 R2-NH R3-N

CH3NH2, (CH3)2NH, (CH3)3N, C2H5NH2 tan tt trong nc

- To mui amoni: R-NH2 + HCl R-NH3+ + Cl-

- C2H5-NH2 + HONO C2H5OH + N2 + H2O C6H5-NH2+HONO +HCl C

050 C6H5N2+Cl- + 2 H2O

N H 2

+ 3 Br 2

N H 2B rB r

B r

+ 3 H B r

8 Aminoaxit H2N-R-COOH

D tan trong nc

- C tnh cht ca nhm NH2 v nhm -COOH

3.4.2. Bi tp: 1. Cho hn hp X gm benzen, phonol v anilin. Hy trnh by phng php ha hc

tch ring tng cht ra dng nguyn cht Gii

OH NH2

dd HCl

OH NH 3Cl

tanloc, tach

NaO HNaOH

NH2

loc, tachtan

ONa

loc, tach

HClloc, tach

OH


27

M t quy trnh: Cho hn hp cht lng vo dung dch HCl d, dung dch b phn lp, chit ring 2 lp:

NH2

+ ClH

NH3Cl

+ Lp nc cha C6H5NH3Cl. Thm dung dch NaOH d vo dung dch trn, lc tch ring anilin khng tan trong nc.

HCl + NaOH NaCl + H2O

NH2

+

NH3Cl

NaOH + NaCl + H2O

+ Phn khng tan gm benzen v phenol Thm dung dch NaOH d vo phn khng tan, cn li phn khng tan l benzen. Tch ring c benzen.

OH

+

ONa

+NaOH H2O

Thm lng d dung dch HCl vo dung dch, tch ring phn khng tan l phenol. OH

+

ONa

+ NaClClH

3. Trnh by phng php ha hc tch ring tng cht trong hn hp cc cht lng sau: CH3CHO, CH3COOH, CH3-O-CH3.

Gii

Ca(OH)2

(CH3COO)2Ca

CH3COOH

CH3CHO, CH3-O-CH3

2) Na

C2H5ONa

H2O

C2H5OH

CH3-O-CH3

H2SO4 1) H2,Ni,t0

CH3CHO CH3COOH CH3-O-CH3

CuO,t0 CH3CHO


28

M t quy trnh: Cho hn hp tc dng vi lng d dung dch Ca(OH)2, un nng thu ly hn hp hi

CH3CHO v CH3-O-CH3. 2 CH3COOH + Ca(OH)2 (CH3COO)2Ca + 2H2O

Ch ha phn dung dch vi H2SO4, chng ct thu c CH3COOH. (CH3COO)2Ca + H2SO4 2 CH3COOH + CaSO4

Hiro ha hn hp hi, ha lng hn hp ri cho tc dng vi Na. Tch ring CH3-O-CH3.

CH3CHO + H2 otNi , CH3CH2OH

CH3CH2OH + Na CH3CH2ONa + H2 Thy phn mui, chng ct thu c ru C2H5OH.

CH3CH2ONa + H2O ot

C2H5OH + NaOH

4. Trnh by phng php ha hc tch ring tng cht trong hn hp sau: axit axetic, ru etylic, ietyl ete, phenol.

Gii M t quy trnh: - Cho hn hp tc dng vi NaOH, un nng thu ly hn hp hi CH3CH2OH v CH3-O-

CH3. Cho hn hp hi tc dng vi Na. Tch ring CH3-O-CH3.

CH3CH2OH + Na CH3CH2ONa + H2 Thy phn mui, chng ct thu c ru C2H5OH.

CH3CH2ONa + H2O C2H5OH + NaOH - Sc kh CO2 vo phn dung dch cha CH3COONa v C6H5ONa, tch ly phenol sinh ra.

C6H5ONa + CO2 + H2O C6H5OH + NaHCO3 - Ch ha dung dch cn li bng dung dch H2SO4, chng ct thu c CH3COOH.

2 CH3COONa + H2SO4 ot CH3COOH + Na2SO4

S tch:

CH3COOH, C2H5OH, CH3-O-CH3, C6H5OH

CH3COONa

C2H5OH, CH3-O-CH3

C2H5ONa

H2SO4

C2H5OH

CH3-O-CH3

NaOH

CH3COONa, C6H5ONa

CO2

C6H5OH

loc, tach

CH3COOH

Na,t0

H2O


29

2. Khi oxi ha ru etylic, ta thu c mt hn hp gm ru etylic, anehit axetic, axit axetic c ln nc. Trnh by phng php ha hc tch ring 3 cht hu c trong hn hp.

Gii

Cho lng d dung dch Ca(OH)2 vo hn hp, un nng hn hp thu hi C2H5OH, CH3CHO.

2 CH3COOH + Ca(OH)2 (CH3COO)2Ca + 2H2O Ch ha phn dung dch vi H2SO4, chng ct thu c CH3COOH.

(CH3COO)2Ca + H2SO4 2 CH3COOH + CaSO4 Ha lng phn hi, cho Na vo hn hp, thm dung mi CCl4 vo th C2H5ONa khng tan. Tch ring C2H5ONa, ri cho vo nc, chng ct thu C2H5OH.

C2H5OH + Na C2H5ONa + H2 C2H5ONa + H2O C2H5OH + NaOH

Chng ct ui dung mi CCl4 trong phn dung dch thu c CH3CHO.

C2H5OH, CH3CHO, CH3COOH

Ca(OH)2

(CH3COO)2Ca

CH3COOH

C2H5OH, CH3CHO

Na

C2H5ONa

H2O

C2H5OH

CH3CHO


30

Chuyn 2: Amin Amino axit - Protein

2.1. Amin

2.1.1. Tnh cht vt l Metylamin, imetylamin, trimetylamin v etylamin l nhng cht kh c mi kh chu, c, d tan trong nc, cc amin ng ng cao hn l cht lng hoc rn, 2.1.2. Cu to phn t v tnh cht ha hc 2.1.2.1. Cu to phn t

Cc amin mch h u c cp electron t do ca nguyn t nit trong nhm chc, do chng c tnh baz. 2.1.2.2. Tnh cht ho hc a. Tnh baz b. Phn ng th nhn thm ca anilin

NH2

+ 3Br2

Br

BrBr

NH2

+ 3HBr

2, 4, 6 tribromanilin

Phn ng ny dng nhn bit anilin. 2.2. Aminoaxit 2.2.1. Khi nim Aminoaxit l nhng hp cht hu c tp chc cha nhm -NH2 v nhm -COOH 2.2.2. Cu to phn t v tnh cht ha hc 2.2.2.1. Cu to phn t V nhm COOH c tnh axit, nhm NH2 c tnh baz nn trng thi kt tinh amino axit tn ti dng ion lng cc. Trong dung dch, dng ion lng cc chuyn mt phn nh thnh dng phn t:

R+

COOHCH

NH3 NH2

COO- RCH

dng ion lng cc dng phn t 2.2.2.2. Tnh cht ha hc Aminoaxit va c tnh cht axit va c tnh baz (lng tnh) a. Tnh baz

HOOC-CH2-NH2 + HCl HOOC-CH2-NH3Cl b. Tnh axit

H2N-CH2COOH + NaOH H2N-CH2COONa + H2O) c. Phn ng trng ngng:

n H2N[CH2]5COOH T (- HN[CH2]5CO -)n + n H2O d.Phn ng este ha ca nhm COOH

2.3. Protein 2.3.1. Khi nim Protein l nhng polipeptit cao phn t c phn t khi t vi chc ngn n vi triu vC.

H2NCH2COOH + C2H5OH H2NCH2COOC2H5 + H2O


31

Protein c chia lm 2 loi: protein n gin v protein phc tp. 2.3.2. Bi tp 1. Mi tanh ca c l hn hp cc amin v mt s tp cht khc. kh mi tanh ca c trc khi nu nn lm nh th no?

A. Ngm c tht lu trong nc amin tan i. B. Ra c bng gim n C. Ra c bng dung dch Na2CO3. D. Ra c bng dung dch thuc tm st trng.

2. Trnh b cch tch ring mi cht khi hn hp sau: a) Hn hp kh: CH4 v CH3NH2 b) Hn hp lng : C6H6, C6H5OH, C6H5NH2

3. Cho 8,9 g - aminoaxit tc dng vi 0,3mol dung dch NaOH thu c dung dch A. tc dng ht vi cc cht trong dung dch A cn 0,4mol dung dch HCl. Bit aminoaxit c 1 nhm NH2 v 1 nhm axit. Tm cng thc cu to ca - aminoaxit trn.

p n: CH3 CH COOH

NH2

4. Aminoaxit cha a nhm COOH v b nhm NH2. Cho 1mol x tc dng ht vi dung dch HCl thu c 169,5g mui. Cho 1mol x tc dng vi dung dch NaOH thu c 177g mui. CTPT ca X l p n:C4H7NO4


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