LE THANH XUAN

, , .. . , , CAC DANG lOAN VA PHUlJNG PHAP GIAI . . ,

HOAHOCII • •

(PHAN HUU CO) . ,

(Tl! LU~N VA TRAC NGHI~M)

.... • • ? ,. ....

BIEN S04N THEO CHU'IJNG TRINH HOA HQC 11 ca BAN VA NANG CAD

r Tcli him !lin tln'r sclu )

NHA XUAT BAN GIAO Dl)C VI~T NAM

- - - -

    

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,..,

PHANI

A. TOM TAT Li THUYET , , ' , ?

B • CAC D~NG TOAN VA PHUONG PHAP GIAI c. aA1 T~P TV LuveN .

' ~ ,1

D ·SAl T~P TONG HQP .,_, ? ~ A

E • CAU HOI TRAC NGHII~M

3

    

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Chu'dng I. DAI Cl1dNG VE HOA HOC Hf1u Cd 0 0

A - TOM TAT Li THUYF~T

§1. HOA HOC HUU CO VA HOP CHKT HCtJ CO

I - DAC DII~M CHUNG . .

- !lop ch«t hi:i'tt co 1 ~1 ho·p ch<'lt cua cacbon (tri:r CO, C0 2 , mu6i

co: , CN ·· . cacbua ... ).

- Thanh ph fin nguyen to trong ho:p chfit hlilt co: C, II, 0, !'\, Cl. ..

- Lien kct giu·a cac nguyen ttr trong h9'p chat hl'ru co 121 lien kct c<'lng hoa tr!.

- I lqp chat hl'ru co dt n6ng ch;'1y, de bay hoi ; sui a nhi¢t ck> thfip ; ft tan

trong H 20 : tan nhicu trong dung moi hu·u co; de ch<1y , de b! nhi¢t phan.

- Clc ph;'m u·ng etta chat hu·u co tiHrong dy ra cham, khcmg ho~m toim, ph<'ti co xl'tc ulc v:1 dun n6ng .

II- PHUONG PI-·IAP TACII Bl~T v/\ TINH CIIFi CHKr JIOlJ CO

I. Chung dit : t<lch de chflt long tan v;to nhau nho sLr kh;\c hi¢t vc Lh) s<'li etta de chflt .

2. Chict : tach cac ch<lt long khCmg tan vao nhau (nhu mr6'c, dtiu thttp). Ch tlt co kh6i ILI'ong ricng th;\p sc n6i len trcn.

3. Kct tinh : t<lch de ch;lt trong hon h(jp rdn dtra trcn d<) tan khac nhau Clla cac Chell.

§2. PHAl\ TICH l\'GUYI~N T6

I- PHAN TICH DINH TINII

l. Xac dlnh C va H : Dot ch<'iy chflt hii'u co, cho s<tn phflm chay 4Lta

CuSO ~ khan v:1 dung d!ch Ca.(OI-1)2 c6 dLr. CuS01 ngam 1-1 20 chuytn thanh

mi1u xanh ; dung d!ch Ca (OH )2 trc1 ncn due vi ph ~m (rng v6'i CO , . Nhu vay

chat hu·u co c6 C, II.

5

2. Xac d~nh N: Dun chat hiiu ca co nita v6i H , SO_. d(tc, h6n hap san

ph<.lm t<.to th~mh co (NH 4 )2

SO_. . Cho (NI-1 4 )2

SO_. tac dung NaOH co khf NH,

hay ra l~1m giay quy u6t hoa xanh . Nhtr v~y chflt hfru ca co nita.

3. Xac d~nh halogen Clo : Dot chat hfru ca co Clo cho COc, H,O,

HCI. HCI bict duac nh<r co dung djch AgN01 (t<.to ket ttta AgCI 1) .

II- PHA:-.J TICH DI~H LUONG . .

1. n~nh Iuqng C, H

Dot chay m(g) chat hfru cacho a(g) CO~ va b(g) H,O

Suy ra : - a '( ) . me _ .. -x L g , 44

%C ::.:= me x 100% Ill

2. l)~nh luqng N :

%H = m 11 x IOOo/r. m

Dot chay hoan roan m(g) chat hfru ca co nita cho COc, H 20 , ~ 2 . Cho

s<ln phflm chay qua blnh dvng KOH d~c thl C02 v~t ·H, O b! hap thu ; c<'>n lai

khf N, ra khoi blnh c6 th~ tfch V 1ft (dktc)

v v n, = --(mol) => m, = - - x 2X

' ' 22,4 ' 22,4

01 N _ m :--: x I 00% !Ol -

m

3. f)~nh luqng 0 :

Sau khi tim %C, %H, %N vlt f/c. Clta cac nguyen t6 kh;'ic c()n lai 1~1 O(!t:

%0 == I 00% - ( %C -t- 0/c II -t- % N + .. . )

§3. C()~G THUC PHAN TV H<_jP CHkr HOlJ CO

* Cong thl'rc phan tl:r etta chflt hfru ca cho hict so nguyen ttr etta d.c nguyen to trong phan tl'r chat hfru ca do.

* C6ng thl'rc dan gi<tn nhat cho bict t i 1¢ so nguyen tv etta de nguyen t6 trong phan IV (ti I~ toi gian Clla cac so nguyen).

6

* C6ng thtrc nguyen (th~rc nghi¢m) 1~1 b6i so cua cong tht'rc dan gi:in.

Vi d1;1 : Chflt hfm ca A c6 3 nguyen to C, H, 0 c6:

+ Ti lc C: H : 0 = I : 2 : I.

+ Cong tht'rc dan gi_;\n ci'ta A: CH , O.

+ C<)ng tht'rc nguyen ci'ta A: (CII,O) . - II

Ncu bict khoi ILrqng ph:ln tt'r ct'ta A (VI du M.\ :c_-, 90dvC) thl suy ra (hrac

cong thCrc phftn ti:r:

(CH,O) c6 M = lJOctvC =->- 30n = 90 - , n _.: 3 - II

I- THifr LAP CONG THUt DON GIAN

.Chflt hfru co A c6 4 nguyen to C, H, 0, N.

Ti 1¢ de nguyen tl'r 1~1 :

m e tn,, m, C:H : O:N = -: m 11 :-' :-

12 16 14

CfcC 9(,0 '!o N = -: o/o H:-:-

12 16 14

II - Tlllfi"r LAP CONG THUt PI-IAN TlJ'

1. Xac d!nh ph~m tu· kh6i

+ Thco d!nh nghla :

+ Thco ti khoi hoi d,_

(M · ·- 29) · Kh,·m~ khi - - ·

B

M =" Kh6i luqng

S6 rriol

MA = MA x d .!\ B

2. Thiet hlp cong thuc phan tu Ti:r cong tht'rc don gi ~m suy ra c6ng tht'rc nguyen va d~ra vao M suy ra

c6ng tht'rc phfm ti:r (xem vf du trcn).

7

§4. eKe TR(;c rHk\\ TV HOP cHKr HDu co

I- TIHJ YI~T CAU TAO 110;\ HOC CLA BUT-Lf:-ROP (I X61)

• N<>i dung hc,>c thuyet

Ibn chtlt hoa hoc ct'ta ph<'\n tLr ch<lt hlilt co phu thu6c vi10 b<tn chfit cua nguyen tLr lf1p th~111h hoi s6 Iuong de nguyen tt'r v~1 h(ti clu tao ho<l hoc cua ph :m ttr ch;\t hCru co cl6.

• Ba Juan diem cua hc,>c thuyet

l. Trong phCm tt'r chflt hCru co, de nguyen tt'r kct hqp v6'i nhau thco nH)t tht.'r tLr nhflt dinh vi'1 thco dung ho<l tri ctia chung . Tlnl· tLr kct hup do chroc goi li't clu tao ho<l hoc. SLr thay ddi thCr tLr kct hop d6 sc tao ra chat m6'i .

2. Trong phCm tLr hqp chCit hu·u co, ctchon. c6 ho<l tr! 4. 1\'guyen tLr cacbon khong nhli'ng c{) thC: lien kct v6'i nplycn tLr ct'ta nguyen t6 khac ma cc)n lien kc·t voi nhau thi'1nh mach cachon .

.3. Tfnh chflt ct'ta hop ch<lt hli'Lt co phu thu6e vi'1o thi'mh ph<in ph<ln tt'r (lxin ch<lt va s6ltrong de nguyen ILl') va CelLI tao ho;l hoc (thu· Ill' lien kct de nguyen llf).

II- CAC LOA! CC)NG THUC CAL TAO

- Cong tht'rc cau tao khai triC:n : Viet cH\y dtt de nguyen ttr V~l de lien kct giu·a chCtng.

\ ' idu: II II I I ,.....II

11-C-C-C=C . I I I '11 I( 11 II

-- (\)ng thu·c du tao thu gon: C vi't de nguyen ttr II lien kct v6'i no viet chung thi'mh nhom .

\ 'fdu:Cli . -- Cil , CH · CIL . -~ -

- Cong thu·c ci'lu tao thu g9n nh<lt : chi viet l icn ke't vi'1 nhom eht.'rc.'

\ 'fdu: ~

1 I 1 - DONG Pf-IAN

I. Ph~in bi~t d()ng d::1ng va d6ng ph<in

·-· \:hu·ng chC{t dong dang Ccl cJU 1<.10 lL!'Ong tll' nhau, tfnh chat hoa hoc

tLrong tu nhau, thimh phfin ph<.in tt'r bon kcm nhau m(Jt ho;k nhicu nhom - Cll , ...

Clc chtlt eking cUng tao ra day d6ng cl ang . Clc chilt c16ng d ~mg c6 ctmg c<"mg

thCrc chung. \i du: Ttlt d ankan cl t u c6 c(l!lg thu·c chung C"H211 " 2 (n ? 1).

- '\hl"rng chill cl6ng pll ;t n li"t nhli'ng ch:it khac nhau nhtrng c6 ctmg c6ng

thu·c ph ft n tt'r.

1. Ph<'m lo~ti de d()ng phan

C6 hai loai c!<lng ph an

o) fJ r)ng ph c!n ('(I'll too ( dr)ng jJ/i (/1/ p/l(i ng) : i':hlittg d6ng ph an khac nhau

ve b ~\ n chJt nh6m chCrc goi Ia d6ng ph ;\ n nh6m chCrc ; kh;lc nhau vt mach

cachon goi l~t clong ph <l n mach cachon ; kh ac nhau vt vi trf nh6m cht:i'c goi l ~t

d6ng ph ~tn vi trf nh6m cht:i"c.

h) Orin ,~ p/f()n l£ i jJ til / ( d( )ng fJh cin k/u)ng gion ) : D6ng ph an lfl p th e' Ut

nhlrng d6ng ph;l n co c<lu tao hoa hoc nhu· nhau (ci:t ng c<ing thCrc cau tao ph <""'tng)

nlnrn o kh ;lc nhau vt su· J1h an b6 trono kh6no (J ian (1 itra c;ic nca uvcn tt'r !ronco c · . c cc c .)

ph iln tt'r tu·c lit kh <"ic nhau vc cCiu tn'tc kht'mg gian ct'ta ph ;l n tt'r.

Dt")ng ph ttn l(tp th e' qucn thu6c tit d6ng ph tm hlnh h()C c is :..._ trans .

f)/)//g p/1(/n hinli /we cis - Irons : !~1 loai cl<)ng ph{in lap th e' chic<> cl 6 i vc1 i ' / hop chtlt c6 li en kct d{J i C = C do mwycn tt'r, nh6m ngU)'en tt'r li en ke·t v~10

. / ' ~ ~

1C ct'ta li en kct cl6i ,·r nhi.i·ng vi trf kha c nhau trong kh(mg gian.

- ~cu hai ngu ye n tt'r gi()ng nh au ho;k hai nh6m ng.uycn tt'r giong nhau

li en kc"t V{IO ltai cacbon Clla li en kct cl6i nam cLillg VC llHll phfa d6i v6i m:n

ph ~111g li en kct d()i goi l ~t cis, nguoc lai , <'1 vc hai ph fa go i l ~t trans .

\ ·i du : II, /II

C =C CII-:" ' e ll .

.1 .)

C I S

II, / CII1

/C=C, l'li1 I I

1 ratJs

- Di t u ki ¢n de' ch~lt hi.i'Lt co co dong ph ftn c is - trans Ut : !lop chCit ph ;\ i ' / -c6 /C = c, "~' tron g hai c ac bon ct'ta lien k. c t d<) i, nH) i cacbon ph~ii li e n kct ha i

ph <'l n tt'r ho~m toan kh;1c nhau.

9

§5. PHAN ( J'NG HOU CO .

I- PHAN LOAI PHAN UNCi HOU CO

1. Phan ung the: M<)t nguyen ti:r hoflc m6t nh6m nguyen ti:r cua phf1n ttr

hfru cob! thay the hoi m<)t nguyen tt'r hoflc nh6m nguyen ttr kh<k .

2. Phan ung cong : Phfm ti:r hfru ca kct hop them · de nguyen ttr hoac

ph fm tt'r khac .

h du : Cl-I , =o CH , -r H , -~--oo CH , - CH , . - - - I ·' -'

3. Phan ung tach : Nguyen ti:r, nh6m nguyen ttr b! tach khoi phfm ttr.

11- cAc KIEU cA.r LIEN K{r cc)NG noA TR!

1. Phan cat d<)ng li : t ~IO ra cac ti~u phfm mang electron IV do goi 1 ~1 g6c

ttr do . G6c t~r do ma electron tlr do a cacbon goi Ia cocho ll_( do.

2. Phan cat di 1i : nguyen ttr do <'un di¢n 16'n tr<':f th~mh anion, nguyen ti:r ell) ;un cli¢n nhb hon th;mh cation. Dien tfch dlrang a nguyen tv cacbon, thl cacbon d6 g9i 1~1 cacbocat ion .

vi du : I . CI.I.CI -- ~' --7 Cl • ..;-cl·

CH, + H + c1• --~ CH~ _._ IICI

CH~ 1~1 g6c cacbon t\[ do

( CH, )3 c-r l ~1 cacbocation .

10

I

I . I

B - cAc D1~NG TOAN VA PHUONG PHAP GIAI

l. eACH THif:T L~P C(>NG THO'C PHAN T(J' CHkr H(JU CO ·

D~tng I I n6T Clf ,~ Y- m (g) C~L\T IICl; CO CH(;~-~~~); tH -~~~;~~~~~-T6-~ I ' I

C, H, 0, \' CliO CO~, 11~0, ~ 1 . B,\1 T0 ,\1\ CliO BIET KII6I r LlfO~G PIL\\' n::. TIM c(>NG TIItrc PHA!\\ T(: 1

___ _ _ _ ____ _ _ _ _______ _______________ _______ ____ __..J

Plurrmg phclp

---- -~11m-kh6i ~-~an~- d-~~1gu;~~~) h<~~c % -khoi ltr<Jng d~~1~~~~ct~-----,

1~

~ m . x 100 m - n x I.., ((T ) :.:::? %C - <.. I c - co. - c -. m

.., ( ) 0 m 11 x I 00 m 11

= n 11

_0 x _ g :.:::? Yo H = --'-'---m

. 1 ( ) c , m , x 100 m, = n, X _X g :.:::? lc N = ----''----. , m

m 0 = m - ( m c + m H i - m, ) '* %0 = I 00'/o - ( (Yc·C + o/t: H + % N)

+ ·nm ti 1¢ C: H ·: 0: r\ suy ra c6ng tht."rc dan gi<in

+lim M .

me· m t) m, C:H:O:]\; -= - - :m 11 :-:-·

12 16 14

%C %0 %N hoac = - : %1-I:-:-

12 16 14

I

I

I

I ! I

L + Suy ra c6ng tht."rc phan tt'r. _j Vi du. Dt dot chay 2, 25g chf\t hfru ca A cht."ra C, H, 0 cfin dung 3,08 1ft 0 2

(dktc) tim duac C02 V~l H 20 v6'i Yeo, = ~ vii ,O (do cung di6u ki~n nhi¢t d<\ ap suflt) . Tim c6ng tht."rc phan ti'r ci'ta A. Biet rang ti khoi hoi

Clt~i A so v6'i II , Ia 45 .

II

Giiii

Dinh iu:tt b:to toan kh6i lmmg suy ra :

D~tt 4

n11 0

=c a =? nco . _,_. -- a :.:. 0, 8a -:...} . . 5

44 x 0, 8a -1 18 x a '-- 6 , 65 --=-> a =--= 0, 125 (mol )

j ll co. =:· OJ~ X 0, 125 = 0, I (mol)

nH n - 0,125 (mol )

me = 0.1 x l2 · 1,2 (g) ; m 11 -= 0, 125 x 2 -=-~ 0.25 (g)

rnu , 2 , 25 -- (1 , 2 + 0, 25) :-:- 0.~ (g ).

C : H : 0 = I' 2 : 0, 25 : ~~ --= 0, I : 0, 25 : 0. 05 .:. 2 : 5 : I

12 16

Cong tht"rc don gi~in etta A: C)-1 )0.

C6ng tht"rc nguyen etta A : ( C ~ lL;O )" c6 M ---= 45 x 2 = 90 (dvC)

-:..--;- 45n - 90 ·-> n -~ 2.

-- ------------------------ --- ------- -- ... ------------ -- ---- - - ------ -- -------- 1

Dang 2 t>6r CIL\ Y l\1(H Tllf: TICII cii:\T lltrt: CO CliO Tllf: TICll CO,, i

TilE TiCH H20, Tllf~ TiCII Nl. TI:\1 CC>NG TJI(IC PJIAN Tt'l - I ------------ ·- ----------- ---- .... ------------------------------ ---- ------------- ______ ___ __j

Plumng pli<ip ----------,------- ---_------- --------------- -----------------------,

+ ·nm th6 tfch boac so mol de ch<tl tuong t"rng r6i the vao phan ung

chay tong quat.

12

    

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---~--------------------------,

( y z) y C H 0 + x + - - ...::. 0 , -~ xCO, + -H , O

X )Z 4 2- -2 -

C 1-1 N1 + (x +t)o, __, xCO, + 2:.H, O + _.!._ N ,

X} 4- -2- ?-(a r11111 ) -

C H 0 N +(x + _r _ _:_)o, -" XCO, -t- 2':.H , O + _.!._N , xyt t 4 2 - -2 - 2-

/ , /(1/ _'\· :

I) * H 20 bj h~lp thu bai cac -chat sau : P20 5, H 2 SO~ d;1c, CaCI 2 khan,

Na , O, K , O, CaO, BaO, dd NaOH, KOH, Ca(OH )2, Ba(OH )2 -

* C0 2 bj hap tht,~ boi cac chat sau : Na :P- K, O, CaO, BaO,

KOH, NaOH, Ba (OH)2 , C.a (OH)2 .

* o, b! hap tht,~ hoi P.

* N2 khong b! hap th~• bai de chat neu trcn .

2) Trong phan trng dot hidrocacbon va amin, ta thay : _II

h . h' , . 1 n0 , t am gta p an ung = nco, + 2 nH ,o

--\l i dt_t / . Dot chay 200cnY' hoi chflt hCru co A ch(ra 3 nguyen to C, H, 0 v6'i

900cm 3 0 2 (lay du) trong khf nhicn ke. Sau . phan ung, th~ tfch hon

hqp khf v~t ·hoi tim dtrqc Ia 1300cm 3. Sau khi cho hoi rnr6'c ngLrng 11,1,

hon hqp khf con 700cm ; va sau khi cho l<)i tiep qua KOH d~c, chi con

I 00cm 3 khf. Tim cong th(rc ph an tv ct'w A.

Gidi

Y0 , con du = I OOcm 3 =_> Y0 , tham gia phim Cmg = 900 - 100 = 800 (em~)

Yeo. = 700 - 100 = 600 (em ' ), YH ,o = l300 - 700 = 600 (cm 3).

DatA 1a C H 0 : • X y Z

( y z) y C,HYO,_ + x +- - - 0, _, xCO, +-H,O 4 2 - - 2 -

200

13

Ta c6 : Y H,u : I OOy = 600 .::.:> y =- 6 ; Yeo, : 200x = 600 ·-=> x = 3 ;

\li du 2. Dot chay hoan to~m hidrocacbon X trong blnh kfn dung tfch I 0 1ft

btmg luqng kh6ng khf H\y gap doi luqng can thiet. Sau phan ung, lam

le;tnh blnh v~ O"C thay ap suat blnh Ia 1 ,948atm . M~t khac, khi hap thy

luqng nl1{1c sinh ra bilng 25m! dung d!ch H~SO-t 98% (D = 1,84g/ml)

duqc dung d!ch H2SO -t 95,75 %.

Biet : - Trong kh6ng khf chi c6 0~ va N 2 v6i ti 1¢ th~ tfch I: 4.

- X khong c6 dong phan.

Tim c6ng lhlrc phan ttr cua X.

Gidi

Dot chay ho~m toan X (CJI}) bai khong khf lay gap d6i luqng can thiet

nen sau phan ung lam l<;tnh v~ O"C h6n hqp khf trong blnh c6 : CO, · sinh ra,

0 2 con du va N 2 cua khong khf kh6ng tham gia phan ung.

14

H6n hap nay c6 so mol Ia : ~~9:8 x 10

= 0, 87 (mol) --· X 273 273

Khoi luqng dd H ~ SO-t ban dau = 25 x U-!4 = 46 (g)

Kh6i lu<,1ng H2SO-t nguyen chat = 4~~:8

:= 45,08 (g)

Khi hap thy H20 thl H2SO-t nguyen chat khong d6i nen :

+ Khoi luang dd H,S04 sau hap thu : 45

•08

x 100

= 47,08 (g) . - . 95,75

+ Khoi Juqng H ~O b! hap th~,~ : 47.08 - 46 = t,m~ (g)

+ S6 mol H~O =-c 1 · 0 ~ ·= 0,06 (mol)

- 18 .

Gia sil so mol X dem dot : a mol.

C.H + (x +r)o~-xco,+ rH,o xy 4- -2-

a -> (x + ~)a ____, xa ---> y2a (mol)

Taco : S6 mol H, O: ya = 0,06 =?- ya = 0,12 - 2

(I)

ya no, ci>ll dtr ::.::: llo, ph.in ling = xa + 4 = xa ·+- 0,03 (mol)

11 0 _ han doll! = 2(xa+0,03) (mol)

Trong kh6ng khf co 20% 0~, 80% N 2

Nen : n, '""~""\If' ~ 111 : 8(xa + 0,03) (n1ol)

tl:r nco, + n:-J , + n0 , dtr := 0,87

=?- xa + 8(xa + 0,03) + xa + 0,03 = 0,87

=?- lOx a = 0, 6 =?- xa = 0, 06 (II)

T , I) , ll) xa 0,06 x 1 u ( va ( =?- - ·= -- =?- - =--= -ya 0,12 y 2 · ·

Cong thuc nguyen cua X Ia ( CH Jl. Vi X khong co dong phan nen chi co n = 2 Ia phu hqp

15

Dang 3 ~--~~.~~ T~~A-~~~M-~~-()N<;THG~-~1.-\~ -~;-(: c-; -;x~~rrt~-z:o -Km c1~o I

'------~ Ls ~~~-~~~~--~!L~\~ ~ :~1 ~- H 10~~-'~~>-~-~~~~-~!:~~--~~~<~~~-~-__j Plur<mg pltap

~ - -. ( cc;~~-~ .v;)-b! h<;p- ;h~bOi ~u~~~~ jc~-~~( ;H~-~=•c ~,-(~II)~.~ I v~y mco, +- m 1L 0 co the tmh duoc nhLr Sclll .

I ) 111 ( ·u, -+-111 H ,o = m I' " \~ CU.\ billh dtru~ dullp di ch -

i 3) m e· l + mH -----'- tn, --- m . 1 1· 1 l .' _, u 1\\:t tu.1 t! ' ~un c lt. l 1.. llll l-! l !c 1

I * Yc CO~ tac dung v6i bazo ki6m (xem l;_ti chLtong 3 "Nh6m cachon" trong

ll sach Cdc dung TU<lll 1·£1 pltuang plulp gi(ii /Joel hue II ( Phdn \'() ur) ci:mg Uic gi;:t). ----------- ------ -·------ -----~---- - ----- ---------- ·--- ---------------- ----- --------

\ ·r du. Dot chay hoan toan mc>t chtlt hfru co A dn 6.72 1ft 0 2 (dktc) chi thu

dLr<Jc C02 vit H 20. Toim bo C02 , H20 dLroc cho vi'to dung d!ch

Ca(OH)2 thu dLf<,)'C lUg kct ltta va dung d!ch sau phan l'rng cho t;k

dung v6i clung d!ch NaOll c6 du thu dLrqc I Og kct ILia ni:'ra. Dung dich

sau ph<ln t'rng c6 khoi I uong nhieu han dung dich Ca ( OH )2 ban dau Ia X,6g. Tim cong tht'rc don gian etta A.

Gidi

Ta c6: mco. + m 1 ~. 0 = m L -i-- m 1 ., 11 ~cu ;tduu~ d ic· h -== 10 --t-8,6 = 18,6 (g) -

VI COc tac dt,mg v6'i Ca (OH) 2 l<;to lOg ket ti:ta C~C01 va dung d!ch sau

phan ung tac dtmg NaOH cho kct tua Ia dung dich muoi ax it Ca(HCO, )2

nen

phan ung xity ra Ia :

C02 + Ca (OH)2 ____, CaC01 l + H 20 (I}

mol 0, I 0, I

2CO~ + Ca(OH)2 -~ Ca(HC03 )2

(2)

mol 0,2 0,1

Ca(HC01 )2

+ 2Na0H ____, CaC01 l +2H 20 ,+ Na 2CO~ (3)

mol 0,1 0,1

16

10 = - = 0, 1 (mol )

100 11 coeo

Ti:r ( l ), (2),(3) =-> nco c=- 0.1 + 0,2 = 0,3 (mol )

_.. __ I 8, 6 -- 0, 3 x 44 _ O 3

( I) ----->"' 11 11 U - - , _ITIO

- 18

A + 0~ ---t C0 2 + H20

Theo djnh luat bc'to toan khoi ltrong, ta c6 :

6, 72 9 ( ) m " = m co, + mH u - m0 _ ::--:: 18,6 - /'1 4

x 32 = g - -,

m e = 0,3 x l2 = 3,6 (g); m 11 = 0.3 x 2 = 0,6 (g);

m 0 = Y- (3, 6 + 0,6) = 4,8 (g)

C: H: 0 = 3·6

: 0,6 : 4

•8

= 0, 3: 0,6 :0,3 = 1:2: I. 12 16

Cong th(rc don gian ci:ta A la CH 20 .

--·--------------------------·---~

Do:~ cu~v CHAT 1~ 0'u ~o c~uA.c\c.~cuvF:N n ) c,H,o,ct vA CHAT HlllJ CO CHVA CAC NGUYEN TO C, H, 0, Na

Plut(fll f? p/[(tp ~--------------------

* m (g)A[C, H, 0 , Cl ]

* m(g)A [C, H, 0, Na]

----- -------------'

2- Hoa HCII 17

Vi du 1. Dot ch<iy ho~m toan 3,61 g chat htru co X thu dLroc hon hop khf g()m

C02, 1-120 V~l HCI. Dan hon hCJp khf nay qua blnh chl'ra dung djch

AgN01 lay du trong HN03 a nhi¢t do th<lp, thu duqc 2,87g kct tl'ta va

blnh chl'ra tang them 2, 17g (cho bict chi c6 1-1 , 0 va HCI bj hap thu).

Dan khf thmlt ra vao IOOml dung djch Ba (OH)2 I M thu duqc 15,76g

ket tt'ta Y. L1y dung djch dun s6i lai cho ket tl'ta nl'ra.

Tim CTPT cua X. Bict Mx < :200 dvC.

Gidi .

HCI + AgN01 __ , AgCll + HN01

2,87 ( ) ( ) :.-::} nfiCI = H-\gCI = 143

S = 0,02 mol ; mH , O j- 1111-lCi = 2,17 g

'

2,17 - 0,02x36,5 ( ) => n = = 0 08 mol

H, O J8 ,

nRa(OH), = 0, I (mol) ; nR;,CO,J = 1 ~~~6 = 0,08 (mol)

Dung djch dun sui cho ket tua Ia dung djch Ba (HC0 3 ) 2 vi v~y C0

2 tac

dung Ba (OH)2 t;:to hai muoi.

18

0,08 ~ 0,08 ~ 0,08

2C0 2 + Ba (OH)c ---> Ba (HC03 ) 2

0,04 ~ 0,1 -- 0,08 :..:0 0,02

nco, = 0,08+0,04 = 0,12 (mol)

• Tim khoi Iuong de nguyen to:

(mol)

(mol)

me = 0,12xl2 = 1,44 (g); mH = 0,08x2 + 0,02xl = 0,18 (g);

mc1 = 0,02x35,5 = 0,71 (g); m 0 = 3, 61 - (1,44 + 0,18+0,71)=1 , 28 (g).

• lim ti I~ nguyen til :

C : H: Cl: O = 1,44 : O, IS: 0, 71 : 1, 28 12 3S,S 16

= 0,12:0,18 : 0,02 :0,08 = 6 : 9: I : 4.

Cong thuc nguyen d1a X : ( C6H9CIO 4 ) " c6 M < 200 suy ra cong thuc

phan til ctla X: C 6H <J CI04 .

Vi du 2. Dot chay ho~m toan S,8g chat hL"ru co A thu duqc 2,6Sg Na2C0_1 ;

2, 2Sg 1-I:_p va 12, I g CO~. lim cong thuc ph an til cl'1a A. Biet dmg

trong phan til A c6 mot nguye n tv oxi .

Gidi

2, 6S 12, I ( ) 2, 2S ? O 2 ( ) m = --x l2 + -x l2 = 36 g · m = - -X - = S g c I 06 44 , ' H 1 8 '

m ~., = 0,025 x 46 = 1, 15 (g); m0 -= S,8 - - (3,6 + 0,2S + l,lS) = 0,8 (g) .

C : H :O : Na = 3' 6 :0,2S: O,S : I,IS 12 16 23

= 0, 3 : 0, 2S : 0, OS : 0, OS = 6 : S : I : 1.

VI trong phan til c6 I nguyen ti'r 0 nen cong thuc phan til cua A Ia

C 6 H 50Na.

D(lng 5 TIM CONG THUC DON GI.<\N CUA MOT CHAT HUU CO CHUA 3

NGUYEN TO C,H,O, KHI BAI TOAN CHO BIET% KHOI LlfQNG

MOT NGUYEN TO HOAC CHO BIET TI L~ THE TiCH HOAC

TONG THE TicH cAc CHAT

Pl11rCJng pluip

Trong thvc te khong c6 cong thuc dan gian vi v~y khi giai toan ta phai

d~t cong thuc phan ti'r chat hli'u CO' Ia e x H YO I roi tim ti I~ nguyen duang toi

gi an X : y : z. Neu dii li~u bai loan cho Ia dol chay chat hiiu CO' va cho ti 1~ th~ I tfch de khf th1 nen gia s ll' dot 1 mol ho~c 1 1ft chat hiiu ca. .

19

Vf du 1. Dot cluly ho~m to~m chflt hfru co X c6 thanh phan C, H, 0 thu dtroc

C02 Y~l H 20, trong d6 Yeo, =% YII.O =c_ % Yo. ph;i ll trll!' (do ci:mg di~u ki~n). nm c6ng thtrc don gian CLia X.

Gidi

D~t cong thCrc phan ti:r chat hfru co Ia CJ1 ) 0 ~..

Gia sLr dot 1 1ft x.

(I ft)

C H 0 +- x +- - - 0 , ___, xCO~ + - H,O ( y z) y

Xyl. 4 2 - -2 -

y z ~x + - -- ~x

4 2 ~r

2

3 3 y 8x Ttr Yeo_.= -

4 VH _. o suy ra: x = -X- => y = -

4 2 3

, 6 6( y ZJ Ttr y ('() = - y(J' h' u· suy ra: X = - X + - -- -' 7 : jl ,Ill I I~ 7 4 2

8x .::::} 7x = 6x + 1,5y - 3z => 3z = J,5y - x = 1,5 X-- X => Z = X . 3

Y~ty x:y:z = 3:8:3

Cong thuc don gian ella X: C 1H 80 , .

Vf dt1 2. a) Tim cong tht.'rc don gi<'m ella A cht.'ra 3 nguyen t6 C, H, 0 va

53,33 % oxi v~ kh6i Iuong.

b) Khi phan tfch chflt hfru co A chCra C, H, 0 thay c6

me+ m 11 = 3,5 m 0 . Tim cong thCrc don gi<in cua A.

c) Dot chay hoan to~m 0,0 15g chat hfru co A chi thu dtroc C0 1 va

H 20 c6 t6ng th~ tfch 22,4ml (dktc). Tim COIJg thCrc don gian cua A.

Gidi

a) D~t c6ng thCrc ph~m ti:r cua A Ia C , HyOz co khoi ltrqng ph an tv la

M (dvC)

16z . 100xl6z 0 % = -x IOO% = 53,33 % => M = = 30z

M 53,33

Ta thay M = l2x + y + 16z = 30z => 12x + y = 14z

20