- Chodung dich NaHS03 vdo honhdp con lai thi (C2H5)20 khong phan iing di/dc tach ra c6n C 2 H 5 C H O phan itng tao ket tua, Ipc lay két tua cho tdc dung vd
b) Axit noda chufc Yc6 cong thijp (C3H403)n , Vi 'jfwn lc *^'
Gidi ' '
a) X CO dang (CHO)„ hay CnH„0„ , }^ PhiTdng trinh phan iJng : C„H„0„ + - ^ 0 2 > nCOi + - H2O
Theo de n x < 6 n c o 2 => n < 6 (n chl'n) fe0tT; n = 2 o CTPT X : C2H2O2 (loai) , ... • 'Wr'•^ n = 4 ^ CTPT X : C4H4O4 • C H - C O O H ' C T C T : II axit butendioic „ C H - C O O H • ^ ^ > ^ f' : ^ ^ f y ' V f r| . n^ ' ' ' • ' • ! ' 5 ' • );i;0,:<: H - ' - ''Êv^. H ...COOH ,.:,/.7(^.r \ • . . • : \ , C=C V .;;1v^v^•^jr;y^^'•|l^^'*^'•.«V«^'^l'* • C=C '('Hf a?.i< / \ • / \ .
HOOC COOH K l i v HOOC H i n , *
axit cis-butendioic (axit maleic) axit trans-butendioic (axit fumaric)
! HQu cd - D6 Xuan Hang
b) Y CO dang (C3H403)n hay C3„H4n03„ hay C , ^ (COOH)3^ ^^^^^^ ,
2 2 2
A x i t no da chiJc c6 dang CmH2m+2-x(COOH); 3n T a c6 m = 2 m + 2 - x = X = • 3n 5n 2 n = 2 m = 3 x = 3 'ij :\ií,h] t'fbíl fJ";-;.!!! i i i , ' ' • •
j;5:>ju s;i:)b :i6 J- !;i«j!f!> -.fw g i i i : , ' 2 P'^íV .G'f.'ijl :<J.^5fi;fiH iCfV Siit/fe 'i^i'sr i X , ; ; X ;..•« f1'i|
Vay C T P T Y : QHxOft hay C3H5(COOH)3. ' axit 1,2,3-propantricacboxylic.
^ C T C T : C H 2 - C H - C H 2 _ _,.
C O O H C O O H C O O H
B ^ i 8. De hidro h6a hoan toan 0,025 mol hon hdp X g o m hai andehit cd k h o i li/dng 1,64 gam, can 1,12 l i t H2 (dktc). M a t khac, k h i cho cung li/dng X tren phan ỉng v d i m o t lifdng d\i dung dich AgNOs trong NH3 t h i thu dtfdc 8,64 gam A g . Cong thỉc cau tao cua hai andehit trong X l a : . 4 j;} jiVj ; ta (
A . O H C- C H 2- C H O va O H C - C H O • ' .o,H»3 ; X Ttr) xP/
B . H - C H O va O H C - C H j - C H O • ,5 ; 4 d f<»nft : ^:^Ub S^.toilT
C. CH2=C(CH3)-CHO va O H C - C H O . o r s / : K <r
D . C H 2= C H- C H 0 va O H C- C H 2- C H O
" Trich de thi tuyen sink Dai hoc khoi B nam 201J''
Gidi
Ta c6: n H , = 0,05 m o l ; nAg = 0,08 mol ' , 7 ,
"2 ' ' ,< ( f {rial .•'I
Ta thay: ^ - - => trong hon hdp X cd 2 Uen ket n => loai B 'Í '
"H2 2
M a t khac: 2 < - ^ = 3,2 < 4
=e> trong X c6 1 andehit đn va 1 andehit 2 chiJc. G o i C T T Q andehit đn chiJc: RCHO (C„H2„-20): a mol
C T T Q andehit 2 chifc: R' ( C H 0 ) 2 (C„H2m_202): b mol
T a cd he: > a + b = 0,025 2a + 4b = 0,08" a = 0,01 .• , . ... b = 0,015 O Ta c 6 : 0 , 0 1 . ( 1 4 n + 14) + 0,015.(14m + 30) = l , 6 4 = > 2 n + 3 m = 15 Ca[, nghỉm phu hdp n = m = 3 => D a p an D .
B a i 9. Hon hdp X gom hai andchit đn chiJc Y \kZ (bict phan t^f k h o i cua Y nho hdn cua Z ) . Cho 1,89 gam X tac dung v d i mOt lifdng diT dung djch AgNOs trong
NH3, sau khi cac phan iJng kc'l thiic, thu dUdc 18,36 gam A g va dung djch Ẹ Cho 274
\ohn bp E tac dung v d i dung dich H C l (dif), ihu dirdc 0,784 l i t CO2 (dktc). Ten c J a Z l a :
y^. andehit propionic B . andehit butiric , ; ,,
C andehit axetic ; j / , D . andehit acrylic r
" Trich de thi tuyen sink Dai hoc khoi B nam 2011"
Giai
Q\io dung dich H C l vao dung dich sau phan iJng trdng gifdng cd C O 2 chiJng to trong dung dich do c6 (NH4)2C03 trong hon hdp andehit ban dSu c6 H C H O Ta c6: T^QO ~ ^^035 m o l ; nAg =0,17 mol
H C H O - . - ^ 4 A g + (NH4)2C03 -> CO2 vsom ,v o r D v-^^^ ;' 0.035 0,14 0,035 ,> ...
RCHO - > 2 A g - . . U . , . 0,015 0,03 , , , v , T .
Ta cd: 0,035.30 + (R + 29).0,015 = 1,89 - > R = 27 (C2H3) '
=> andehit c6n l a i la: CH2= C H - CHO: andehit acrylic => D a p a n D .
Bai 10. Hon hdp G gom hai andehit X va Y , trong do M ^ < My < 1,6 M , . Dot chiiy hon hdp G thu diTdc CO2 va H2O cd so mol b^ng nhaụ Cho 0,10 mol hon hdp G v^o dung dich A g N 0 3 trong NH3 thu diTdc 0,25 mol A g . Tong so cac nguyen tuT
trong mpt phan tuf Y la v
^ ••••• I.•: t)'-'
Ạ 10 B . 7. C. 6. D . 9.
0, jir;^ ^ , ^ "Trichdi thi tuyen sinh Canđnfindm 2011"
Gidi
D6't chay hon hdp G thu dtfdc CO2 va H2O co so mol bhng nhau => 2 andehit trong G la no, đn chiJc.
Cho 0,10 mol hon hdp G vao dung dich AgNOs trong NH3 thu difdc 0,25 mol A g .
V§y trong G c6 1 andehit Ik H C H O ( X ) => 30 < M y < 30.1,6 = 48 ' => M y = 44 => R + 29 = 44 =i> R = 15 (CHj) =>Ym C H 3 C H O => D a p an B .
11. M o t chat huru cd X (C.HyO,) c6 ti khoi so vdi metan la 4,25. Biet 0,2 mol X tac dung vij:a du vdi 0,3 mol Ag20/NH3 (0,6 mol AgNOs/NHj) thu diTdc 43,2g Ag. CTCT dung vij:a du vdi 0,3 mol Ag20/NH3 (0,6 mol AgNOs/NHj) thu diTdc 43,2g Ag. CTCT cua X la:
A . H C = C- C H 2 - C H O ' ^ ^ K ' * B. H 3 C- C = C- C H 0
C. H2C = C = C H - C H O D . HCOO - CH2 - C = C H ú '
•1 Gidi . /•( r^titAM •
Ta c6: n . = = 0,4 mol '''^ '•''^'^ .^3K«>i^l^A ,<uuftt ixu,:^ c,il fk^'c
108 mfk'i - ^ ' . A ; ^ filih mlt ...^H^l SA0-:U f()v'.,;:;A flM,'
nvd\] uijiig va ymuuij piiap giai Hua n^ic 11 HUU C O - UP xuan Hiing
- ^ = — = 2 => X CO 1 nhom CHỌ >,
nx 0,2 'J
Goi cong thu-c tong quat cua X la R C H O .
De cho: M x = 16.4.25 = 68 o MR + 29 = 68 => MR = 39 ( C 3 H 3 - ) '
"Ag _ 0,4 _ 4 . Mat khac
chiJng to trong X c6 chiJa lien ket ba (C = C ) dau mach.
=> C T C T dung cua X la H C ^ C - C H j - C H O => Dap an A . ^
Bai 12. Dot chay hôn toan x mol axit cacboxylic E , thu dufdc y m o l C O 2 va z nioi H 2 O (vdi z = y - X). Cho x mol E tac dung v d i NaHCOj (diT) thu dtfdc y m o l CỌ, Ten cua E la
Ạ axit acrylic. B. axit oxalic. C . axit adipic. D . axit fomic.
"Trich de thi tuyen sink Dai hoc khdi A nam 2011
* Cdchl: ; v i v j .a; ..nMiit,
Goi cong thiJc cua axit E : C,HyO, ' -' ' - 0 (tM A
i C x H y O, - » x C 0 2 + - H 2 O , , , , rt,^. » t
•if: , • , ^ 2 i,pM. s::y:ytl^iM%Ami^} imih'
'\^'Hi ax —a y T a c d : — a = ax - a =J> y = 2 x - 2 Axit E c6 27t => lôi D 'f^'xtnolE + N a H C O g ' - ^ y m o i c O j l ^' ^ ,i ^ n => E c6 so C b^ng so chifc , > • . . ;> E + 0 2 ^ y m o l C 0 2 J .4 u t - // ' 1 t w rt ' I t ' 1 tf \i = > B l a ( C O O H)2=>DapanB. • Cdch 2: ' • '"k'' •••• ' t<. i ^ - " "axit ^ S 6 ' n h 6 m C O O H == - / „ i f , w H > ' " i n,,;, X So C trung binh = = ^ "axit . _ " C 0 2 _ y^ "axit X
=> Chat E c6 so C = so nh6m chijfc => loai A, C
A x i t fomic chay c6 n ^ o j = n H 2 0= > l o a i D =>DapanB. ^ Bai 13. Hon hdp Z gom hai axit cacboxylic đn chiJc X va Y ( M x > M y ) c6 tong
khoi liTdng \k 8,2 gam. Cho Z t^c dung vilfa du v d i dung dich N a O H , thu diTd"-
dung dich chiJa 11,5 gam muoị M a t khdc, neu cho Z tac dung v d i mpt li/dng dung dich AgNOa trong NH3, thu difdc 21,6 gam A g . Cong thiJc va phan trani