86
dung d i c h A : CH3COOK + H2SO4 —> CH3COOH + KHSO4
• - K h o i luang CH3COOH l a m = 60 X 0,02 = 1,2 (gam).
Bai 10. G o i cong thufc cua amino axit l a (H2N)nR(C00H)„i c6 so m o l la 0,1 X 0,2 = 0,02 (mol). (H2N)„R(COOH)^ + m N a O H > (H2N)„R(C00Na)„, + mH20 T a c6: nNaOH = m x 0,02 = 0,08 x 0,25 => m = 1. (H2N)„R(C00H)^ + n H C l > (CIH3N)„R(C00H)„ T a c6: nHci = n x 0,02 = 0,08 x 0,5 =i> n = 2. M a t k h d c k h o i li/ang m o l cua A : M = 2 X 16 + R + 45 = 146 R = 69 la- C 5 H 9 < V a y a m i n o a x i t l a (H2N)2C5H9-COOH. n H 2 N - C 5 H 9 ( N H 2) C O O H . trungngutig ^ 4 NH-C5H9(NH2)-CO 4- n + nHgO 108 Bdl DUSNG HdA HQC 12 CHl/dNG V.
DAI Cl/dNG VE KIM LOAI
• •
Ạ KIEN THLfC CAN NH6
1. Tinh chat chung cua kim logi
Tinh chat vat li chung cua kim logi nhú tinh deo, dan dien, dan nhiet, dnh kim chu yen do cdc electron ti{ do trong kim logi gay rạ
Tinh chat hoa hoc chung cua kim logi la tinh khit, do nguyen tii kim logi dS nhúdng electron hoa tri trong cdc phan úng hoa hoc.
2. Cap oxi hoa-khvt cua kim loqi
Dang oxi hoa (M"'^) va dgng khii (M) cua cung mot kim logi tgo nen mot cap oxi hoa-khit, giúa chung c6 moi quan he:
M"^ + ne , . ^ M
(cap oxi hoa-khit cua kim logi dMc viet la M"*/M)
3. Pin dien hoa: Id thiet hi trong do ndng litcfng cua phan ring oxi
hda-khii chuyen thdnh dien ndng. Pin dien hoa tgo bdi hai cap oxi hoa-khif, trong do:
- O cúc dm xdy ra sif oxi hoa chat khiị ~ d cUc diidng xdy ra sii khiị
4. Day the dien cifc chudn cua kim logi
- Dien cite hidro chudn cd the dien cúc chudn quy itdc bdng 0,00V. The dien cúc chudn cua kim logi bdng sud't dien dong cua pin tgo bdi dien cúc hidro chudn vd dien ci(c kim logi nhiing vdo dung dich nnidi cua no vdi ndng do ion kim logi bang IM.
~ The dien ciic chudn cua cap oxi hda - khii cua mot kim logi ndo do
CO gid tri cdng Idn thi khd ndng oxi hoa cua cation kim logi cdng mgnh vd khd ndng khit cua kim logi cdng yeu vd ngúcfc Igị
~ Kim logi trong cap oxi hoa - khii cd the dien cite chudn nhd ban khii diicfc cation kim logi trong cap oxi hoa - khii cd the dien cifc
ul chudn Idn hdn. Kim logi trong cap oxi hda - khii cd the dien cifc chudn dm khii diigc ion cua dung dich axit.
~ Phan ling giiia hai cap oxi hoa - khit xdy ra theo quy tdc: Chat 0x1 hda cua cap oxi hda - khii cd the dien ci(c chudn Idn hdn se oxi hda
- Suat dien dgng chudn cua pin dien hoa (E|;.,J bdng the dien cite chudn cua cite ditang trit di the dien cifc chudn cua am; ludn luon CO gid tri dúcfng.
Vi du: Pin dien hoa tgo bdi hai cap oxi hoa - khif va c6 Fe Cu the dien cite chudn ghi nhit sau: E" = - 0,44V ; É^ = +0 34V
- Phan ifng xdy ra d trong pin: . Cu^* + Fe > Fê* + Cu - d cite ditc/ng xay ra sii khit: Cif* + 2e > Cu - U cite am xdy ra sit oxi hoa: Fe > Fê* + 2e
- Sudt dien dong cua pin: E||._^ = 0,34V - (-0.44V) = 0,781'
5. Syt dien phan
a) Rhai niem: Sit dien phan la qua trinh oxi hoa - khit xdy ra d bo mat cac dien cite khi cho dong dien mot chieu di qua chat dien li mat cac dien cite khi cho dong dien mot chieu di qua chat dien li nong chdy hoac dung dich chat dien lị
b) Phan d^ng hoa hoc & cac dien ci/c trong thiet hi dien phan
- O catot (cite -) xdy ra sit khif, chdt c6 tinh oxi hoa mgnh hdn thi de hi khit.
Vi du: d catot c6 mat ion Cu^* vd phan tit H2O, cac ion Cu^^ c6 tinh oxi hoa mgnh hdn se hi khit thdnh Cụ
- O anot (cite +) xdy ra sit oxi hoa, chdt c6 tinh khit mgnh hdn thi de hi oxi hoạ
Vi du: d anot c6 mat cua phan tit H2O, cac ion SÔ" vd NO:; . Cac phan tif H2O CO tinh khit mgnh hdn se hi oxi hoa thdnh O2 vd ion W. Neu anot (cite +) khong trd thi anot tan.
6. Sif an mbn kim logi
a) SU an mbn hoa hoc va sit an mbn dien hoa
- Giong nhau: ban chdt cua sit an mdn hoa hoc vd sit an mdn dien hoa la phan I'tng oxi hoa - khit.