4 M A n.,: + Chieu ciid phan ung oxi hoa-khu: Phan ung oxi hoa-khu dien ra theo chieu tao thanh chat khu va chat oxi hoa yeu hon.. + Do vay, trong day di^n hoa, chat khu cua cap dung t
Trang 1Cam nang 6n luy^n thi dgi hgc 18 chuy§n d§ H6a hqc - Nguyen Van Hk\
Lai gidi:
Cac phan u n g hoa hoc: Q|J
gf 3Cu + 8HN03{loang) > 3Cu(N03)2 + 2 N O + 4H2O
Cu + mN03{dac,nguoi) > Cu(N03)2 + 2NO2 + 2H2O > ^ j J i o y i f ,
Lwu y: V o i d u n g dich hon h(7p K N O 3 + H2SO4 loang, trong d u n g dich c6 chua
cac ion (do H2SO4 phan li) va N O 3 (do KNOa phan li) nen c6 tinh chat
giohg HNO3 loang —> hoa tan duoc Cu theo p h u o n g trinh:
3 C u + 8 H * + 2 N O 3 — 3 C u 2 * + 2 N p + H 2 O ' ,
^ D a p a n C
V i dv 16: Cho 6,4 gam bpt Cu tac d y n g v o i 100ml d u n g dich X h o n hop
tjii g o m HNOa 1,2M va H 2 S O 4 0,6M Sau k h i cac phan u n g xay ra hoan toan,
sinh ra V l i t k h i N O (san p h a m k h u d u y nhat, 6 dktc) Gia t r i ciia V lajtj
rlrrA.1,344, B 1,008 C 1,792 , ^^^^y^, D 1,120 j -j^^i
Lai gidi:
n Cu = 6,4
•• 0,1 m o i ' x ^ i ^ _ , „f , ; ' : 8 f t f i | •• ' , nf^j
64
Nhan xet: k h i axit H N O 3 c6 mat d o n g thoi v o i axit H2SO4 loang thi l u g n g
trong d u n g d i c h la do 2 axit p h a n li ra - > G i a i theo p h u o n g trinh ion
V i dv 17: Cho 3,36 gam M g tac d y n g v o i d u n g dich HNOa d u , t h u dugc 0,448 lit
khi N2 t i n h khiet (dktc) Co can d u n g dich sau phan l i n g t h u dugc m gam
m u o i khan Gia t r i ciia m la
C h a t oxi hoa: 2N*5 + jOe > N2; 2N^5 + ge > N H 4 N a •
;gn A p d y n g bao toan electron: 2 n ^ g = 10 n ^ j + 8 nNH4N03 j b
m u o i NH4NO3
Vx dv 18: N h i i n g m o t la k i m loai M (hoa t r i 2) c6 khoi l u g i i g 5 gam vao 200 m l
dung dich A g N 0 3 0,1M cho den k h i phan u n g hoan toan t h u dugc chat ran
X va d u n g dich Y chua 1,89 gam m u o i K i m loai M la j^ ^-^^^^^ ^
A M g B Cu C Fe D Zn^,^^^^ ,
Lai gidi: ^ ,Rb^.r«i*ir>ofm^,
N^jflM xet: Trong cac dap an, k i m loai c6 khoi l u g n g m o l Ion nhat la Z n ->
nj^ > — > n A g i v j o 3 AgNOa phan u n g he't.i-ii J - M J ^ u i ; hiuaf^ a u j >^J.:,
, , , .0 ihA-:> ,(§.'•/ u&A fBr!:> rifiedl < j
Phan u n g hoa hoc: ; , , ^ ^ ^^^^^ ,
M + 2AgNOa > M(NOa)2 + 2 A g e o r i i x o f f e d : K V
M o l : 0,01 <- 0,02 - » 0,01 -'[^-^t,^'"
M M ( N 0 3 ) 2 = ^ ^ M = 65 (Zn) ^ Dap an D 1
V i 19: Cho m gam Z n vao 100 m l d u n g dich g o m Cu(N03)2 0,1M va AgNOa
0,2M Sau k h i cac phan u n g xay ra hoan toan, t h u du(?c chat ran X Cho X tac d y n g v o i d u n g dich H2SO4 (loang, du), thu dugc 0,448 l i t k h i (dktc) Gia
t r i c u a m l a : ^,(1 ^„ „ : i ; ,
A 2,60 B.1,30 C.0,65 * D 3,90
Lai gidi: <oD •
Cach 1: nAgNOs = 0/02 m o l ; ncu(N03 )2 = 0,01 m o l ; n H j = 0,02 - " f r u ri
NMn xet: Cho X + H C l d u giai phong H2 X chua Z n -> Z n con d u (s, i :
Phan l i n g hoa hoc: *::^A ^^9^
Z n + 2 A g N 0 3 > Zn(N03)2 + 2 A g /F''
Zn + Cu(NOa)2 > Zn(N03)2 + Cu '^-^r^'h&tki m ^i^yi:o':) <
Zn + H2SO4 > ZnS04 + H2 > y r M rijl rifiq dnhl g n w j i ! ' ?
nAi = "^^^^°^ + ncu(N03)2 + " H 2 = 0,04 m o l -> mzn = 2,6 gam | 15,, j , , -> Dap a n A - inW m M i i X :! ub
man xet: Z n tac d u n g v o i 3 chat oxi hoa la Ag% Cu^^ v a '^^^^^'
Bao toan electron: iJ * • 2nz„ = In + + 2n^ 2+ + ln„+ = 0,02 + 0,02 + 0,04 = 0,08
nzn= 0,04 m o l mzn= 2,6 gam -> Dap an A yfcgmib :»6i W^'' '' '
181
Trang 2Cám nang 6n luyQn thi djii hpc 18 chuy6n dg Hoa hpc - Nguyen Van Hk\
2 D A Y D I E N H O A C U A K I M L O A I
ạ Day difn hoa ,, , , , „ ^ ,
K Na •••• Mg Al Zn Fe Ni ^ Sn ^ Pb ^
2H^^ C u ^ % _ F e ^ ^ ^ • -
-.-'.o -H2 Cu Fê"" Ag nfiriq i r i i n9b !ifb;MI,0(iOH§A rbib
b Y nghia cua day di^n hoa
Tir trai sang phai, tinh khu ciia cac kim loai giant dan, con tinh oxi hoa ciia
cac ion kim loai tang dan
c S u dung day d i f n hoa ^'^ ' u u i jt.j ^ a u i i 4 M A n.,:
+ Chieu ciid phan ung oxi hoa-khu: Phan ung oxi hoa-khu dien ra theo chieu
tao thanh chat khu va chat oxi hoa yeu hon
+ Do vay, trong day di^n hoa, chat khu cua cap dung trudc se tac dung duoc
voi chat oxi hoa ciia cap dung saụ
Fê* Fê^ ^, „ _ _
IT^ F ?
Vtdu 1: > -> Tinh khii Fe > Fê*; tinh oxi hoa Fê* > Fê*
Co xay ra phan ling: Fe + 2Fê* >^ Fê^ + ZFê* ^"^ <?1
, Fe + Fe2(S04)3 > 3FeS04; Fe + 2Fe(N03)3 > 3Fe(N03)2 j ^ ' ! ^
Cv^+ Fê*
Vt du 2: — — > — — -» Tinh khii Cu > Fê^; h'nh oxi hoa Fê* > Cu^\ '
Co xay ra phan ling: Cu + 2Fe3* > Cu^* + ZFê*
Phuang trinh phan tii: Cu + Fe2(S04)3 > CuS04 + 2FeS04, j l '
Hay: Cu + 2FeCl3 > C u C h + 2FeCl2 v^^v
^« 3: ^ - 2 ^ > ^ Tinh khii Fê^ > A g ; tinh oxi hoa Ag^ > Fê*
—> Co xay ra phan ling: Fê* + Ag^ > Vê* + Ag ^'^''^^^O + n
Phuong trinh phan tii: Fe(N03)2 + AgN03 > Fe(N03)3 + A g
Vi dy 1: X la kim loai phan ling duQ-c voi dung djch H2SO4 loang, Y la kim loai
tac dung dugc voi dung dich Fe(NC)3)3 Trong day di^n hoa, c|ip Fê/Fê*
diing truoc cap AgVAg Hai kim loai X, Y Ian lugt la
Ạ Fe, Cụ B Cu, Fẹ C Ag, Mg D Mg, Ag ,
Loai B va C do Cu va Ag khong tac dung voi dung djch ^2804 loang
Y la kim loai tac dung dugc vai dung dich Fe(N03)3 - > Loai D ^ *
' dV 2: Cho 1,68 gam hot Fe vao 100ml dung dich chxia FeCb 0 ,2M va CuCh 0,1M
iChuay deu tai phan ling hoan toan thu dugc dung dich X va m gam chat ran Gia tri ciia m la
^0,56 B.1,12 COM D.1,20. j ^ t o , ,
Laigidi: y ntio) mod riBi s o H :?! uh
np^= 0,03 mol; npecis = 0,02 mol; ncuClz = ÓOl "^ol. j ,Qg;|.| Vi^j^ y n u l
iV/jfl« xet: Do cap ~—> ~2+ ^'"'^ ^ P^^"
Fe + 2FeCl3 > 3FeCl2 '^'^'^^ ' ^^^^^^^^
Mol- 0 01 -> 0 02 ' + ^'^^^ '-^'^^ "^^"^^^^ ° "-^ ° ^^•^'^'^^
• + CuCl2 > FeCl2 -H CuW^^S'^^'*^^^:'^^^^^^'^^'^^^'''^^^
Mol: aoi <- aoi •H'^^/^^'^ ^ T " '
Chat ran gom: Fe du = 0,01 mol; Cu = 0,01 mol ^ m = 1,20 gant ' "
^ D a p a n D
Vi dv 3: Cho cac phan ling xay ra sau day: ' " F.(*02)S9^ + uD
AgN03 + Fe(N03)2 > Fe(N03)3 + Ag (1) lỌQ 10,0
Mn+2HC1 >MnCl2 + H2 f - ^ S t , (2) O d f r o ^ - f n v
Day cac ion dugc sap xep theo chieu tang dan tinh oxi hoa la ^'^^ J"^*'
Ạ Mn^^ H^ Fe3^ Ag Ag^ Fê Mn^\ \
C Ag^, M n ^ H*, ¥ệi ''", ,' D Mn^\^ Fê\ •'['
Laigidi:
Nhqn xet: Tu (1) -> Cap diing truoc cap — ^ '
Fe Ag ^ J
Tu (2) ^ cap diing truoc cap
4? • , M n H2 , ^ v( 63 cOVIttifXfi irlM :iVt '
Thu tu trong day dỉn hoa: - ^ > - ^ ^ ^ V
-> Tinh oxi hoa tang dan theo thii ty: Mn^* < < Fê" < Ag* ' Dap an Ạ '
dy 4: y j tri ciia mgt so cap oxi hoa-khii dugc sap xep nhu sau: Fê^/Fe, Cu^VCu, Fe3VFe2^ AgVAg, CI2 /2CI- Trong cac chat sau: Cu, AgN03, CI2,
chat nao tac dung voi dung dich Fe(N03)2:
Ạ Cu, AgNOs, CI2 B AgN03,Cl2 C CI2 D Cu, AgNOs
183
Trang 3dm nang On luyjn thi dgi hqc IS cliuyen ae M O J _ _ ^ [ y ih _ « a ^ i a i
LOT ^J'ai;
Lww y: Fe(N03)2 c6 the tac d\ing vai ca chát khvr va chát oxi hoạ Dieu ki^n Q
day la chat khu diing truoc FêVFe; chat oxi hoa dung sau Fê^/Fê*
, Theo bai cho: Khong c6 cap nao dung truoc FêVFe va c6 hai cap dung sâ
}, Fe3"/Fe2* —> Dap an B
Cac phan ung hoa hoc: Fe(N03)2 + AgN03 > Fe(N03)3 + Ag
6Fe(N03)2 + 3Cl2 > 4Fe(N03)3 + 2FeCl3
V i du 5: Hoa tan hoan toan 9,92 gam h6n hgp bot Fe304 va Cu trong 160ml
dung dich H2SO4 I M (loang) Sau khi cac phan ling xay ra hoan toan, thy
dugc dung dich X (khong con axit du) Co can X thu dugc m gam muoj
' khan Gia tri ciia m la
A 19,68 B 16,64 C 10,72 D 23,36
G9isomol:Fe304 = a;Cu = b.Theobai:232a + 64b = 9,92 1 ^ fQ^O ị
Nhan xet: Chi c6 Fe304 phan ung true tiep v6i axit Cac phan ling hoa hgc:
Fe304 + 4H2SO4 > FeS04 + Fe2(S04)3 + 2H2O ^ iu,u;i<,
V i d v 6: Hoa tan hoan toan 1,12 gam bgt Fe t r o n g 100ml dung dich gom
HNO3 I M va H2SO4 0,3M thu dugc dung dich X Dung dich X c6 the tac
dung voi toi da m gam bgt Cụ Biet khi N O la san pham khu duy nhát ciia
N*^ trong cac qua trinh tren Gia trj cua m la
A 1,92 B.2,56 C a64 ' D 3,20
n F e = =0,02 mol - - *^ , f ' U:v^,:
56
Nhqn xet: Khi axit HNO3 c6 mat dong thoi vai axit H2SO4 loang thi lugng
H* trong dung djch la do 2 axit phan li ra -> Giai theo phuang trinh ion
V = n R N O g + 2 n H 2 S 0 4 = 0,1 + 2.0,03 = 0,16 mol
n = 0,1 mol; n 2- = 0,03 mol TIRIJ i ịx^j'irtntf •<
Phuang trinh ion nit ggn: /^
Fe + 4H* + N O ; ^ Fê + N O + 2H2O ,, , i j ^ S u
Mol: 0,02 <- 0,08 0,02 -> 0,02 • * ' ' %iinilv
Khi d i o X tac dung vai Cu: 45|,D.ịdD,d^^,, ,,JA,IJ3
Cty TNHH MTV DWH Khang Vigt
3Cu + 8H* + 2 N O ; > 3Cu2* + 2NO + 4H2O '''^•^ ""^^^
r'Mol: a03 ^ 0,08 ^ 0,02"'^' ^ ' 0,03 T ^ ' ^ - -^-^^-''^
Cu + 2Fe3* > Cu^* + 2Fe2* ,
Mol: 0,01 <- 0,02 ri>^> snub IrnnCS. oftv Ife rtirsH} iDrn -^miuV-A
' m = 0,04.64 = 2,56 gam Dap an B
Vi dV 7: Cho 2,24 gam Fe vao 200 ml dung dich gom NaN03 0,3M va H2SO4
0,6M, thu dugc dung dich X Cho mot thanh Cu vao X, sau Idii cac phan
^ g hoan toan, thay khoi lugng thanh Cu giam m gam Gia tri ciia m la
X CO chua: n^ 3+ = 0,04; n„+ = 0,08; n^,^_ = 0,02; Nâ va SỐ'''**^ ' '
3Cu + 8H* + 2 N O i > 3Cu2* + 2NO + 4H2O itHOsV
Mol: 0,03 0,08 0,02 ^1 £10',./,' H
Cu + 2Fe3^ > Cu2* + 2Fe2^ • - 3"^'^- "^'"-J''
Mol: 0,02 0,04 ' • -> ncu = 0,03 + 0,02 = 0,05 mol -» mcu = 0,05.64 = 3,2 gam ^ Dap an Ạ
-3 B A I T A P O N L U Y E N y^ airiqr'^iiJ.'ib**.•uec^ M i u. (UH^:/ •
Bai 1: Dot chay hoan toan 7,2 gam kim loai M (hoa tri 2) bang mot lugng vira
dii la 0,25 mol hon hgp khi CI2 va O2, thu dugc 23 gam chat ran Kim loai M
la
Ạ Bẹ B Cụ C Cạ '»T->rr^D Mg
Bai 2: Dot nong 1,40 gam hon hgp X gom Cu, Zn va M g trong khi oxi, thu dugc 2,04 gam hon hgp Y gom 3 oxit De hoa tan het Y can toi thieu V ml dung
Ạ 40 B.30 C.20 D 50
^ai 3: Cho 1,68 gam kim loai R (hoa tri n khong doi) tac dyng voi 0,025 mol O2,
thu dugc chat rMn X Hoa tan het X trong dung djch HCl, thu dugc 0,448 lit
khi H 2 (dktc) Kim loai R la cU,u ,, j ,
Ạ Cạ B Zn C Al D Mg
4: Hoa tan het 20,88 gam mgt oxit sat bang dung dich H2SO4 dac, nong thu
^irgc dung dich X va 3,248 lit khi SO2 (san pham khu duy nhat, 6 dktc) Co
X, thu dugc m gam muoi sunfat khan Gia trj cua m la
Ạ 52,2 B.54,0 C.58,0 D 48,4 ' ' ' 185
Trang 4Cim nang On luy^n thi d?i hqc 18 chuy6n <3i H6a hpc - Nguygn Van HSi
Bai 5: N g a m m o t d i n h sat trong 200ml d u n g dich CuS04 a mol/1 Sau k h i
p h a n l i n g ke't thiic, lay d i n h sat ra khoi d u n g dich, rira sach, say kho va
d e m can, thay k h o i l u g n g d i n h sat tang 0,8 gam Gia t r i cua a la
A 0,50 B 0,25 C 0,30 D 0,20
Bai 6: N h i i n g m o t thanh sat vao 200ml d u n g dich g o m Cu(N03)2 0,2M va
AgNOa 0,1M Sau mot thoi gian lay thanh k i m loai ra, riia sach lam kho,
thay khoi lugng thanh sat tang 1,76 gam K h o i l u ^ n g sat da phan u n g la
A 1,12 gam B 1,40 gam C 1,68 gam D 1,96 gam
Bai 7: Cho hon hgp hot gom 1,3 gam Z n va 2,8 gam Fe vao 400ml d u n g dich
CuS04 a mol/1 sau phan u n g hoan toan t h u dugc 4,4 gam chat ran X g o m hai
k i m loai Gia trj cua a la '''^^'^
A 0,20 B.0,30 C.0,15 " c O i / b aiO " ' i r
Bai 8: Cho hon hop X gom Fe203, Z n O va Cu tac d u n g v o i d u n g dich H C l (du)
thu dugc d u n g dich Y va phan khong tan Z Cho Y tac d y n g v o i d u n g dich
N a O H (loang, d u ) thu dugc ket tiia
A Fe(OH)2, Cu(OH)2 va Zn(OH)2 B Fe(OH )3 va Zn(OH)2
C Fe(OH)2 va Cu(OH)2 )MS + D Fe(OH)3 - 'HH + uDt
Bai 9: Cho 0,12 m o l Fe tac d u n g v o i 0,4 m o l axit H N O 3 t o i phan u n g hoan toan,
thu dugc d u n g dich Y chua m gam m u o i va k h i N O (san p h a m k h u duy
nhat) Gia t r i ciia m la (bie't cap Fe^VFe d u n g trudc cap Fe^VFe^*)
A 25,32 B.24,2 C 29,04 D 10,80 '
Bai 10: Cho hon hgp bgt g o m 0,27 gam A l va 0,56 gam Fe vao 550 m l dung
dich AgNOs 0,1M Sau k h i cac phan u n g xay ra hoan toan, t h u dugc m
g a m chat ran Gia t r i ciia m la (bie't cap Fe^^/Fe^* d u n g truac A g V A g ) : •
{ A 5,94 B 6,48 C 3,24. "D. 5,40
4 H I / 6 N G D A N - L O I G I A I -BD ^ 9^ >
B^j 1 ffV vr*i r^'?' '' Y nrirf "rVf r n E § Ot^,| § n 6 n i o Q :S'
Nhqn xet: Bao toan khoi lugng: 7,2 + m o j + n i c i j = 23 ^ ^P^^ "Of^ ^^J^
Cty TNHH MTV D W H Khang Vijt
l^han xet: Bao toan khoi lugng: m o j = 2,04 - 1,40 = 0,64 gam ; , , ) / , „ , A n
Vay: n o = ^ = 0,04 m o l ^ n^2- = a04 m o l '^"^
K h i cho oxit k i m loai tac d u n g v o i axit, ion O^" trong oxit se ket hgp v o i H *
trong axit tao thanh H 2 O theo p h u o n g trinh:
n = 0,14 R = 12n Vay n = 2 va R = 24 (Mg) ^ Dap an D ^ ^^^'i^
\!iii:t ^ uJ ^0<irlX ^.-r:^- j^O^ij^ + n X
Bai 4:
Nhqn xet: Oxit sSt FexOy tac d u n g v a i H 2 S O 4 d^c, none S O 2 t h i oxit la FeO hoac Fe304
Cac e m lu'u y rang 1 m o l FeO hoac Fe304 deu chua 1 m o l Fe^* nen deu c6
kha nang n h u o n g 1 m o l electron, do do:
3 248 ' ^0,0»j^oa./:)« V
- n F e , O y = 2nso2 ^ Hp^^Qy = 2 - - ^ = 0,145 m o l 3 q s G <
M F e , O y= 7 r ^ = 72 (FeO) " ~
-B a o t o a n n g u y e n t o F e : 2FeO > Fe2(S04 )3 x - 20,0)d5 = x.m :DBrW I G } ' mFe2(so4)3= 0,145.^.400 = 58 gam ^ Dap an C Onh^hQ <^ ^
^ach 1: Giai theo p h u o n g t r i n h hoa hgc: - -^.^ OHd +
fO-Fe + CuS04 > fO-FeS04 + C u ^ j^pjc ,^ ,
M o l : 0,2a < - 0,2a v ,r>,u a2a ^^^^ ^ i l u 3 : l u
^ 6 1 l u g u g d i n h sat tang = 64.0,2a - 56.0,2a = 1,6a ^ ^yj^^^ j
1,6a = 0 , 8 a = 0,5 ^ Dap an A , , , 3 , , t
"^n 2: Tang giam khoi l u o n g : _ , ,
I m o l F e > I m o l C u - > K h o i l u g n g tang 8 gam gmih i oi1
O ' l m o l ^ tang as gam x i v u i ' J
~* " C U S O 4 " F e = 0,1 m o l - > 0,2a = 0,1 a = 0,5 ^ Dap an A ^ qj.<-f <
Trang 5Ca'm nang On luy^n thi dgi hpc 18 chuy6n dg H6a hqc - Nguygn Van H&\
N/ian xet: K h i cho X + H C l d u t h i CO 2 chat tac dving true tiep:
Fe203 + 6HC1 > 2FeCl3 + 3H2O o i i i e i O ; :
Cho Y + dung dich N a O H du ^ Hai ket tua la Fe(OH)2 va Cu(OH)2.'"
Lieu y 2: Zn(OH)2 luong tinh nen da tan trong N a O H du
_-> Fe d u = 0,02 m o l va tiep tuc p h a n u n g v o i Fe(N03)3: «mf i n mtiA' f,
Fe + 2Fe(N03)3 >3Fe(N03)2 u u i m f i eriq v >
M o l : 0,02 0,04 0,06 ' r^jp srisi/
Sau p h a n u n g : Fe(N03 )3 d u = 0,06 mol; Fe(N03)2 = 0,06 m o l fifjiiH
_ > m = 0,06.242 + 0,06.180 = 25,32 gam. , kith ^Xffit> m^ji noni n/
Fe'^"^ Ae'*' — (a-ifoo^OBiH
Nhdn xet: D o cap — j — > — > xay ra phan u n g :
ififi (r) •~;6dri n^ib riom njl B I VGX '§b n?i>! uyrb lit,
r j ^ u p qert nfiij^ 'jfiori) u s d n i^ v q^h Dt^it 3uy qaiJ (£) ^ucff^ ohn >
"Hb Ififb hvfl ri-jtb j^nub JOfirt grfib o^v gnurfn ivjv*
.jfcol miA nbm ah j^jidrii rf')'- •
iriq j\w ^ grtorf-t fn*.- ,5 , 'Ml'.'!" ! nri>l '•>'' '
Trang 6Ca'm nang 6n luyCn thi dai hpc 18 chuy6n dS H6a hpc - Nguygn Van HSi
C h u y e n de 8
AN M(m K I M LOAI - IHltU €Hlt KIM LOAI
1. A N M O N K I M L O A I ^-^^
a Khai ni?m - ' ' grm nsffq oyt qsii 6v lorn S0;0 = tih •
Su pha h u y k i m loai hoac h o p k i m do tac d u n g hoa hoc cua m o i truorig
x u n g quanh goi la su an m o n k i m loai
b Phan loai ^-''("OVi'v-r^ -.vrHf rtsrfr:
An m o n k i m loai dugc chia thanh 2 loai chinh: A n m o n hoa hoc va an m6n
d i ^ n hoa. •„-•!•> • ^ i s-: • - f/.'^ - >5 ^ ff'^v*^ 4'^'^
+ An mon hoa hoc:
A n m o n hoa hpc la sy pha h u y k i m loai do k i m loai phan u n g hoa hoc v6i
axit hoac cac chat k h i (hoi) 6 nhiet dp cao
Dac diem ciia an m o n hoa hoc la qua trinh oxi hoa-khu, electron dupe chuyen
tryc tie'p t u chat oxi hoa deh chat k h u len khong phat sinh dong di§n
Vidu\ , ,.s;Vt«nf ^'-S'iffW • £0.0 •<-^-10,0 ;{o:
Fe + H2S04(io3ng) > FeS04 + H2 +€^q
3Fe + 2O2 '" > Fe304 - 'v ,gA^ ^ " ^ ^ ' ' "
+ An mon dim hod:
A n m o n d i ^ n hoa la s u pha h u y k i m loai do k i m loai tie'p xiic v o i d u n g dich
chat dien l i tao nen d o n g electron chuyen d a i t u cue a m sang cue d u o n g va
phat sinh d o n g d i f n
Co che an m o n dien hoa: •.^_.,f^y.y :M _y.^;_,^^ v \ <» i-^ , , ^ ^
V i d u CO 2 tarn k i m loai Z n va C u dup-c n h u n g vao d u n g d i c h H2SO4
Tai cue am (anot), Z n ( k i m loai m a n h hon) b i oxi hoa: ,
Z n - 2e > Zn^*
, Tai cue d u o n g (eatot), ion H"^ chuyen den be m a t C u de nhan electron t u cue
a m chuyen t o i va b i oxi hoa tao thanh k h i H2:
2 H * + 2e > H2
Ba dieu k i ^ n de xay ra an m o n d i f n hoa: (1) Co hai k i m loai c6 ban chat
khac nhau, (2) tie'p xiic tryc tie'p v a i nhau (hoac gian tie'p qua day dan) va (3)
dupe n h i i n g vao cimg m p t d u n g dich chua chat d i ^ n l i
c Cach chong an mon kim loai:
+ Phuomg phdp bdo ve be mat:
D i m g n h u n g chat ben v o i m o i t r u o n g p h u len be mat k i m loai D o la:
D u n g son cho'ng gi, vecni, dau mo, trang men, p h u h p p chat poiime
M a m p t so' k i m loai ben n h u crom, niken, dong, kem, thie'c len be mat kif^
loai can bao ve
Cty TNHH MTV DWH Khang Vijt
+ Phuang phdp dien hoa:
No'i k i m loai can bao ve v o i 1 tarn k i m loai khac c6 t i n h k h u m a n h h o n
V i dv, de bao v? v6 tau bien bang thep, n g u d i ta gan vao v6 tau (phan chim trong nuoc bien) n h i i n g tarn kem K h i tau hoat dong, tarn k e m b i an m o n dan, v6 tau dupe bao v^ Sau m p t thoi gian n g u a i ta thay cac tarn k e m khac
VI D U M A U
Vi dvi 1: K h i dieu che hidro t u Z n va d u n g dich H2SO4 loang, neu them vao
m p t vai gipt d u n g dich CuS04 t h i tha'y k h i H2 thoat ra m g n h hon Ban chat cua h i ^ n t u p n g tren la ^^"t"' ' ^ '
A A n m o n dien hoa ^' • ' ' B A n m o n hoa hpc 'i'i
C u thoat ra b a m tren hat Z n nen thoa man 3 dieu kien ve qua t r i n h an m o n
d i f n hoa: Co hai k i m loai khac nhau (Zn - Cu), tie'p xuc true tie'p v o i nhau (Cu b a m vao Z n ) va cung n h u n g trong d u n g dich chat dien l i (H2SO4 loang)
D o do xay ra qua t r i n h an m o n dien hoa —> Dap an A
Vi 2: T r u o n g h p p nao sau day xay ra an mon di§n hoa: "'^"^ ^- '
A Thep de t r o n g k h o n g k h i kho, nong ,
B K e m de t r o n g d u n g dich H2SO4 loang
C Sat chay trong k h o n g k h i
D V 6 tau bien bSng thep ngam trong nuoc b i e n ^ 8 " " * ^ '
Laigidi: ^mi >nkdaoBoo r
Loai A, C: Thep de trong k h o n g k h i kho nong hoac dot chay s^t trong
k h o n g k h i - » Deu bj an m o n hoa hpc. SOB^E EJJ9>1£ • •
Loai B: K e m de t r o n g axit H2SO4 loang Kem bj an m o n hoa hpc i
—> Dap an D
Luu y: V 6 tau bang thep la h p p k i m Fe - C (chua 2 d i | n cue c6 ban chat khac
nhau va tie'p xiic trye tie'p v o i nhau) va ciing tie'p xiic v a i d u n g djch d i ^ n l i (nuae bien) nen xay ra an m o n dien hoa :,;
V i d v 3: Cho cac h p p k i m sau: Cu-Fe (I); Zn-Fe (II); Fe-C (III); Sn-Fe (IV) K h i
tie'p xiic v o i d u n g djeh chat dien l i t h i cac h p p k i m m a t r o n g do Fe bi an
m o n truoc la:
A I , I I va IV B I , I I v a i n C I , I I I v a I V D I I , I I I va IV
1Q1
Trang 7C^m nang 6n luy^n thi dgi hpc 18 chuySn 66 Hoa hpc - Nguygn Van HSi
Lai gidi:
Nhan xet: Trong cac qua trinh an mon dien hoa, kim loai m ^ h han se bi an
^ mon —> Fe bi an mon truoc khi no la chat khu manh hon (dong vai tro la
anot - cue am)
Trong cac cap (I), (III), (IV) thi Fe deu manh han, rieng cap (II) thi Zn manh
hon
• ^ D a p a n C , , • , :>;;.f:,,,, , ,,•
V i di^ 4: Gang bi an mon dien hoa trong khong khi am Qua trinh kliir xay ra tren
•n- be mat aia gang la: ,fe^,^|,.,B,M>i.#«i: -)1»ft»l^s*&i^.»v:t<,r
A O2 + 2H2O + 4e > 4 0 H - ' B 2H2O + 4e > O2 +
40H-C Fe > Fe2* +2e D Fe > Fe^* +3e
Lai gidi:
Thep la hop kim Fe-C (vdi mot so nguyen to'khac) Khi tie'p xiic voi khong
khi am (c6 chiia chat di^n li) se xuat hi^n qua trinh an mon di?n hoa Fe la
' cue am (bi an mon), C la cue duong se xay ra su khu
O2 + 2H2O + 4e > 4 0 H - ^nfi^YGx6«<)au^frl9.flj^/l>tm-•
—> Dap an A
Luu y: Cac em de chon riham B vi bo qua vai tro cua chat oxi hoa la oxi
khong khi
V i du 5: Co 4 dung dich: a) HCl, b) CuCh, c) FeCb, d) HCl c6 Ian CuCh
Nhiing vao moi dung dich mpt thanh Fe nguyen chat So truong hop xuat
hien an mon dien hoa la: ,
A.O B 1 C.2 D.3
Laigiai, yu,<)(i!M"
Nhan xet:
+ Khi nhiing thanh Fe vao cac dung dich HCl va FeCk, Fe bi an mon hoa hpc
theo cac phan ling:
gr Fe + 2HC1 > FeCk + H2 '
.:o-Fe + 2.:o-FeCl3 > S.:o-FeCk ,r;
+ Khi rihiing Fe vao dung dich CuCk se CO qua trinh: 0
Fe + CuCk > Cu + FeCk
Jfi K i m loai Cu sinh ra bam vao Fe tao thanh cap di#n eye nhiing trong dung
•' dich dien l i la CuCk nen xay ra an mon dien hoa
+ Tuong t u voi dung dich HCl c6 l l n CuCk, Fe se day Cu theo phan ling:
ifl Fe + CuCk > Cu + FeCk
—> Cu bam vao Fe —> Xay ra an mon dien hoa ; W
Chat khu la C: Khu dugc cac oxit cua kim loai tir Zn va tao thanh khi CO
Chat khu la Al: khu dugc cac oxit ciia kim loai tu Cr
Thuy luyen la phuang phap dieu che kim loai bang each dimg kim loai
m^nh hon day kim loai yeu hon ra khoi dung dich muo'i
hieu y: Do'i voi cac kim loai kiem va kiem tho (tru Be, Mg) khi tac dung vai
dung dich muoi, chiing se tac dung vai nuoc -> Dung dich baza, bazo tao
thanh c6 the tac dung tie'p voi muo'i:
Vi du cho N a kim loai vao dung dich CuS04 xay ra cac phuang trinh:
2Na + 2H2O > 2 N a O H + H2 2NaOH + CuS04 > Na2S04 + Cu(OH)2^
Phttong phap di^n phan
Bien phan nong chay
Day la phuang phap dieu che cac kim loai manh Cac kim loai kiem, kiem
tho thuang dieu che bang phuang phap dien phan nong chay muoi
halogenua; rieng Al dugc dieu che'bang phuang phap di§n ph?n nong chay AkOs voi duang cue bang than chi o
2Ak03 ''P"" > 4A1 + 3O2
Dien phan dung dich
Day la phuang phap dieu che cac kim loai trung binh va yeu tu cac dung dich muo'i tuang ling ciia chiing
iLuong hap 1: Goc axit tham gia di^n phan:
CuCk _ i P ^ Cu + Ck Iruang hop 2: Goc axit khong tham gia dien phan:
2
4AgN03 + 2H2O — ^ 2 ^ 4Ag + O2 + 4HN03
193
Trang 8Ca'm nang 6n luyen thi dgl hoc 18 chuyen d8 H6a hpc - Nguyin Van Hi\
D i n h luat Faraday (tinh lup-ng chat t h u dugc 6 cac d i | n cue): m = A l t
nP
m: K h o i l u g n g chat t h u dug-c a d i ^ n cue (gam)
A: Kho'i Itfong m o l nguyen t u (mol.phan tu) ciia chat t h u dug'c a d i ^ n cue
n: So electron trao d o i m a ion d a nhan de t^o thanh n g u y e n t u (phan tu)
t u o n g u n g 6 dien cue
I : C u o n g d p d o n g dien (ampe) t: thai gian di#n p h a n (giay)
F: H a n g so Faraday (F = 96.500) i ' ^ 1 m,- v
Lieu y: T u cong thue d i n h luat Faraday, so mol electron trao d o i t r o n g qua
t r i n h d i ^ n phan d u o c t i n h theo eong thue: n g = — n = —
Day la cong thue giiip giai nhanh chong nhieu bai tonffcfien phan
V i D V M A U _ • ,^.nn
V i dxf 1: Cho l u o n g k h i H2 (du) qua hon hgp cae oxit CuO, Fe263, A I 2 O 3 , MgO
n u n g a nhiet d o eao Sau phan u n g hon hgp ran con lai la:
A C u , FeO, A I 2 O 3 , M g O B C u , Fe, A l , M g
C C u , Fe, A l , M g O ' D Cu, Fe, AhOa, M g O V ,
rfn-.i,,.,, Lai giai:
Nhan xet: Day la each dieu che k i m loai bang p h u a n g phap n h i f t luyen 6
n h i ^ t d p cao, k h i H 2 C 6 the k h u cac oxit k i m loai d i m g sau Z n
6 bai nay, k h i H2 k h u dupe cac oxit CuO, Fe203 thanh C u , Fe; k h o n g khir
dupe M g O , A I 2 O 3 - > Dap an D
V i d^ 2: Cho l u o n g k h i C O (du) d i qua 12 gam h o n h p p g o m Fe203 v a MgO
n u n g n o n g den k h i phan u n g hoan toan, t h u dupe 9,6 g a m chat ran Khoi
l u p n g Fe203 c6 trong h o n h p p ban dau la: „,,^ , ,^ ^f,;^'
A 8 gam B 16 gam C 24 gam D 12 gam
Nhan xet: K h i C O chi k h u dupe Fe203 theo phan l i n g :
rnpejOa ~ 0/05.160 = 8 gam -> Dap an A
V i d\ 3: K h u hoan toan m o t oxit sat FcxOy a nhi^t dp cao can vira d u V lit kl^'
C O (dktc), sau phan u n g t h u dupe 5,6 gam Fe v a 0,15 m o l k h i CO2 Cong
thiic cua oxit sSt v a gia t r i cua V la
A Fe304 va 3,36 , , ,,, B Fe304 v a 4,48 - m »• EOMS
C FeO v a 2,24 - s ^ D Fe203 va 3,36 ;
Lm giai:
ach 1: Giai theo p h u o n g t r i n h hoa hpc
FexOy + y C O — ^ xFe + yC02
Nhan xet: XXQ ^^xit) = " c o = "002 = 0,15 -> Vco2 = 3,36
M a t khae: n^^: TYQ = 0,5:0,15 = 2:3 -> Fe203 -> Dap an D
V i dv 4: N g a m m o t la k e m t r o n g 100 m l d u n g dich CuS04 a mol/1 Sau k h i
p h a n u n g ke't thue, lay la k e m ra k h o i d u n g dich, rua sach, say kho v a dem can, thay kho'i l u p n g la kem giam 0,05 gam Gia t r i cua a la
Vi dv 5: K h i d i ^ n p h a n d u n g dich CuS04 ( v o i d i ^ n eye tro) t h i cac qua t r i n h
xay ra 6 r y e am v a cue d u o n g Ian l u p t la
A O x i hoa H2O v a k h u ion Cu^* B K h i r i o n Cu^"^ v a oxi hoa H2O
C K h u i o n Cu^* va oxi hoa i o n SO 4 " D K h u H2O va oxi hoa i o n Cu^*
Lai giai: ,r
Cyc a m (eatot) eo i o n Cu^* v a H2O I o n Cu^* bi di$n phan:
Cu2* + 2e > C u {Qua trinh khie) Cye d u o n g (anot) eo H2O va i o n SO 4 —> H2O b i d i ^ n phan:
H2O >-O2 + 4 H * + 2 e
2
(Qua trinh oxi hoa) 80,6 " : l o i
—> Dap an B
Ghi nha cau tha: A n h la A n o t n h u o n g e, Em la Catot n h a n e thoi ma
V i dy 6: D i e n phan 800 m l d u n g dich AgNOa 0,1M v o i dien cue t r a trong t gia,
cuong d p dong di?n k h o n g d o i 1,34A (hi^u sua't qua t r i n h d i ^ n phan la 100%), t h u dupe chat ran X, d u n g dich Y v a k h i Z Cho m o t t h a n h Fe vao Y, sau k h i cac p h a n u n g ke't thiic thay k h o i l u p n g thanh Fe tang them 2,36 gam va c 6 k h i N O (san p h a m k h u d u y nhat ciia N"^"^) bay ra Gia t r i eiia t la
A 0,8 B 1,2 C.1,0 D.0,3
.- " 195
Trang 9dm nang On luy^n thi dgi hpc 18 chuy6n di H6a hpc - NguyJn Van HSi
Lot gidi:
Phan ling dien phan dung dich AgNOs: ' " |
2AgN03 + H2O —^Edd_) 2Ag + ^ 0 2 + 2HN03
Mol: 2a "'^ ' ' ' ' 2a ' 2a ' '^^'
Nhqn xet: Vi khoi lug-ng Fe tang them nen thanh Fe dupe Ag bam vao-^ y
chiia A g N 0 3 - > AgNOs chua bi di^n phan het* l«l^/;v.'
-Cac phan ung khi cho Fe vao Y:
Fe + 4HN03 > Fe(N03)3 + NO + 2 H 2 0 , o y a n i ^ M '
Can luu y Fe tac dung voi Fe(N03)3: / -l^ j '
Fe + 2Fe(N03)3 > 3Fe(N03)2 rVrt',
Mol: 0,25a •(- 0,5a /^^v r, ''^ " - ^ ' '',i»Viii W.KWMi *
Fe + 2AgN03 > Fe(N03)2 + 2Ag ' ' ' ofex*
Mol: b <- 2b - > 'jsufTO-f 2b
Theo bai: 2b.l08 - 56(0,75a + b) = 2,36 w: a'.:
Matkhac: nAgNOa = 2a + 2b = 0,08 a =0,02 mol; b =0,02 moi £ jo;
ne= 2a = 0,04 ^ = 0/04 mol ^ t = 2880 giay = 0,8 gio ^ Dap an A
V i 7: Di?n phan dung dich X gom 0,16 mol NaCl va 0,24 mol CuS04 (dien cue
tra, mang ngan xop) den khi tha'y thoat ra 6 anot 2,688 lit khi (dktc) thi ngung
di|n phan Khoi luong dung dich sau dien phan giam di bao nhieu gam?
A 6,96 gam B 12,08 gam C 17,20 gam D 5,12 gam
LMgidi:
2,688 „ \ ,
n t = = 0,12 mol. , „ , v ^ , , ,
22,4
Phan ling "quy doi" gia dinh: i*-^ v
CuS04 + 2NaCl > CuCh + Na2S04 ^^nwib D
Mol: 0,08 <- 0,16 0,08 0,08
^ X gom cac muoi: CuCh = 0,08 mol; CuS04 = 0,16 mol va Na2S04 = 0,08 mol
Thii tu dien phan nhu sau:
A Phuong phap hoa hoe B Phuong phap difn hoa , ,
C Phuong phap bao ve be mat D Phuong phap tao hpp kim khong gi
Bai 2: Co 4 dung dieh rieng biet: CuS04, ZnCh, FeCb, AgNOa Nhiing vao moi dung dich mpt thanh Ni So truong hpp xuat hif n an mon di^n hoa la
A 2 .B.4 C.3 D 1
Bai 3: Trong pin di^n hoa Zn-Cu, qua trinh khir trong pin la
A Zn^* + 2e > Zn B Cu^* + 2e > Cu ^
C Cu > Cu2* + 2e D Zn > Zn^* + 2e
Bai 4: Tien hanh boh thi nghi^m sau: , (1) Nhiing thanh Fe vao dung djch FeCb; ^
(2) Nhiing thanh Fe vao dung dich CuS04; ^' ' (3) Nhiing thanh Cu vao dung djch FeCb; ^^"^ "'"'^ ' " \
(4) Cho thanh Fe tiep xiic voi thanh Cu roi nhiing vao dung dich HCl
So truong hpp xuat hi^n an mon di^n hoa la
dupe 21,4 gam chat ran Y Cho Y tac dung voi dung dich HNO3 loang, du
thu dupe V lit NO (san pham khu duy nha't, 6 dktc) Gia tri eiia V la:
0: A 2,24 B.4,48 C 6,72 D 8,96
^ 7: Tien hanh phan ung nhi^t nhom voi h6n hpp bpt gom A l va CuO, thu
dupe eha't ran X Chia X thanh hai phan bang nhau ,j i"-
+ Phan 1 tac dung vua dii voi 100ml durg dich NaOH I M
^ Phan 2 tac dyng voi dung djch HNO3 loang, du thu dupe V lit NO (san
; pham khii duy nha't, o dktc)
Gia tri eiia V la: j
A 2,24 B.4,48 C 6,72 D 8,96
^ai 8: Hon hpp Y gom CuO, FeO va Fe203 Hoa tan hoan toan 27,6 gam Y bang
dung dich H2SO4, thu dupe 59,6 gam muol M§t khae, ne'u khii hoan toan
27,6 gam X can vua dii V lit khi CO (dktc) Gia trj eua V la
A 4,48 B.6,72 C 8,96 D 5,60
,.CI J 't.8<^,>
Trang 10CJm nang 6n luy^n thi dgi hpc 18 chuygn dg H6a hqc - Nguygn Van HJi
pai 9: Nhung mot la kim loai R (hoa tri 2) c6 khoi lugng 10 gam vao 200ml dung
dich CuS04 0,1M cho den khi phan ling hoan toan thu duoc chat rAn X va
dung dich Y chua 3,22 gam muoi K i m loai M la
A Mg ^'^ B Be C Fe D Z n
pai 10: Cho hon hgp gom Mg va Fe vao dung djch C u C h deh khi cac phan virig
hoan toan, thu dug-c dung dich X gom hai muo'i va chat ran Y gom hai kim
loai Hai muoi trong X la
A M g C h v a F e C h ^ , B M g C h va CuCh
C F e C h va CuCb D M g C h va FeCh
pai 11: Nhung mot thanh Mg vao 100ml dung dich gom Cu(N03)2 0,3M va
AgNOa 0,2M Sau mpt thoi gian lay thanh kim loai ra, rua sach lam kho,
thay khoi luong thanh Mg tang 2,72 gam Khoi lugng Mg da phan ung la
A 1,20 gam B 0,72 gam C 0,48 gam D 0,96 gam
pai 12: Cho 1,3 gam hot Z n vao 100ml dung dich chua hon hgp gom AgNOa
0,2M va Cu(N03)2 0,5M Sau khi cac phan ung xay ra hoan toan, thu dugc
dung dich X va m gam chat ran Y Gia tri cua m la: ^
A 2,80 B.5,36 C 4,08 D 2,16
pai 13: Cho hon hgp bpt gom 1,3 gam Z n va 3,2 gam C u vao 200ml dung dich
^ AgNOa a mol/1 sau phan ung hoan toan thu dugc 12,08 gam chat ran X gom
hai kim lo^i Gia tri cua a la T'lMj
A 0,20 B.0,30 C.0,15 • D 0,50
pai 14: Cho 4,1 gam hon hgp X gom Z n va Fe vao 200ml dung dich CuS04 0,2M
, Sau khi cac phan ihig xay ra hoan toan, Igc thu dugc 4,24 gam chat ran Y va
dung dich Z chiia hai muoi Khoi lugng cua Z n trong X la:
A 0,65 gam B 1,3 gam C 1,95 gam D 2,6 gam
pai 15: Di^n phan 200ml dung dich gom AgNOs 0,5M va Cu(N03)2 I M bang
li dong dif n mgt chieu vol cuong dg dong dif n 2,68A trong thai gian 4 gia
Kho'i lugng kim loai thoat ra 6 catot la:
A 20,4 gam B 23,6 gam C 10,2 gam D 11,8 gam/'
pai 16: Di#n phan dung dich hon hgp chua 0,15 mol CuS04 va 0,1 mol H C l
trong thai gian 2 gio vai dong difn c6 cuong dg la 1,34A Biet hifu suat ciia
qua trinh di|n phan la 100% Khoi lugng kim loai thoat ra tai catot la:
A 6,4 gam B 3,2 gam C 12,8 gam D 9,6 gam
Bai 17: Di?n phan dung dich X gom 0,2 mol N a C l va 0,2 mol CuS04 (di^n afc
tro, mang ngan xo'p) den khi khoi lugng dung dich giam di 17,5 gam thi
ngung di^n phan The rich khi (dktc) thoat ra 6 anot la
A 1,12 lit B 1,68 lit C 2,24 lit D 2,80 lit
^ Cty TNHH MTV DVVH Khang Vigt
T H I / O ' N G D A N - L C J I G I A I Rai ^'
Sn trang len Fe se bao phii be mat tranh cho Fe bi an mon Day la phvrang phap bao ve be mat —> Dap an C
luu y: day cac em de chgn nham dap an B Can nho rang phuang phap
dien hoa la de bao v§ kim loai, can ghep no vol kim loai m^nh hon
2: :, , ,,.v.,i if-y •••:> • r:-<i '':vr
-+ Nhiing N i vao cac dung dich CuS04 hoac AgNOa thi N i se day C u va A g ra, cac kim loai nay lai bam tren be mat N i Tao thanh cac cap pin di^n Ni -
C u va N i - A g —> A n mon dien hoa
+ Nhung N i vao dung dich Z n C h thi khong xay ra phan ling - > N i khong bi
Zn > Zn2- + 2e " ' Catot (cue duang): Ion Cu^* den nhan electron (qua M n h khii ion Cu^*):
Cu2* + 2e > C u ' i A ^^:tt.: y ^_ i_-_Q|i:>,,iA igrm riE/iq tj.u Dap an B ••:>iMJ%;' ' • '•
BM4:
Nhan xet: 6 thi nghi^m 2 (Fe day C u va C u bam vao Fe) va 4 (Fe tiep xuc vol Cu) -> Deu sinh ra cap di|n c\fc Fe - C u , tiep xiic tryctiep vai nhau va ciing
nhung trong mgt dung dich di|n li Xuat hi|n an mon di|n hoa -> Dap an B
Lieu y: 6 thi nghi?m 1 va 3, Fe b} an mon hoa hgc theo cac phan ling:
|,, Fe + 2FeCla > 3FeCl2 -fy?^ vt;;/''^
C u + 2FeCla > C u C k + 2FeCh f + Xo^»^ •
nAl= ^ = 0,5 mol; n^^^o, = ^ = ^'^ " H 2 ~ = 0'^
2A1 + Fe203 — ^ AI2O3 + 2Fe Mol: 2a < - a i >m 2a - > nAidu = 0 , 5 - 2 a Khi cho X + N a O H du: • ^ , ,
A l + N a O H + H 2 O > NaAICh + | H 2 U S , ^ • U 0 >
J?/
199
Trang 11Ca'm nang On luy^n thi dgi hpc 18 chuy§n 6i Hoa hgc - Nguyjn VSn Hai
AI2O3 + 2NaOH > 2NaA102 + 2H2O
Al^ FeaOg X ^ " ^ ° 3 > AI3^, pe^^ ; r ^ ,
Nhan thdy: tu tr^ng thai dau tien den trang thai cuoi ciing thi: So'oxi hoa ciia
Fe khong doi (luon la +3), con so oxi hoa ciia A l tang tit 0 len +3 ,, ,^
A p dyng bao toan electron: ng=3nAi =3nNO HC*
-> n ^ o = r»Al= 0/2 mol -> V = 0,2.22,4 = 4,48 lit -> Dap an B
Bai7:
Nhan xet:
Khi cho phan 1 + NaOH, tat ca A l va AI2O3 deu chuyen vao hp-p chtYt
NaA102 -> A p dyng bao toan nguyen to'Na va A l ta c6:
nNaOH="NaA102 = " A l nAi= 0,1.1 = 0,1 mol
So do phan ling: A l , C u O — ^ X ) A l ^ \
Nhan thdy: T u trang thai dau tien den trang thai cuoi cung thi: So oxi hoa
ciia C u khong doi (luon la +2), con so'oxi hoa cua A l tang tu 0 len +3
Ap dyng bao toan electron: = Sn^i = Sn^o
-> n ^ o = " A r 0,1 mol ^ V = 0,1.22,4 = 2,24 lit
-> Dap an A
Bai8:
Nhan xet: ^,v,,Wj./«-i5 «ir/;,
Khi cho X + H2SO4 thi oxit chuyen thanh muoi sunfat va mot ion O^" trong
oxit dupe thay the bang mpt ion SO 4" '
1 mol 02- > 1 mol S O ^ ~ -> Khoi lu(?ng tang 96 - 1 6 = 80 gam '
a mol tang 59,6-27,6 = 32 gam
32
-> a = — =0,4 mol -> no (x) = 0,4 mol
80
Khi cho 27,6 gam X tac dyng voi C O thi: no (x) = nco= 0,4 mol
Vco= 0,4.22,4 = 8,96 lit -> Dap an C '
Nhan xet: Y gom 2 kim l o ^ —> Y chiia Mg hoac Fe Mpt kim loai con du ->
CuCk het Loai B va C
M|t khac: Do tinh khii Mg > Fe —> Mg phan ling truac roi moi den Fe
Gia sii Mg con d u —> Fe con nguyen va C u bi "day" ra het -> Chat rSn X gom 3 kim lo^ii —> Dieu gia sii la sai
Mg phan ling het va Fe phan ling mpt phan —> Y gom Fe du va Cu
-> Hai muoi trong X la MgCh va FeCh -> Dap an A
Bai 11:
"AgN03 = 0,02 mol; ncu(N03)2 = 0,03 mol •? >
Nhan xet: Tinh oxi hoa Ag* > Cu^* AgNOa phan ling trudc roi moi den
Cu(N03)2 »i>UV!iJ C/»?T S S > , • , f TlfWC{" &fo «r v
Phan ling hoa hpc: \ i r i * JOP;
Mg + 2AgN03 > Mg(N03)2 + 2Ag Mol: 0,01 <- 0,02 0,02 -> mtang = 2,16-0,24 = l,92g
Mg +CU(N03)2 > Mg(IJ03)2 + C u
Mol: a <— a a mtang = (64-24)a = 40a
Theo bai: m Mg tang = 2,72 1,92 + 40a = 2,72
-> a = 0,02 mol — > mMg (pu) = 24.(0,01 + a) = 0,72 gam
-> Dap an B
Bai 12: ' ' ^ ' ^ ' ^ '
= 0,02 mol; n^^j^o^ = 0,02 mol; ncu(N03)2 = 0,05 mol
Phuong trinh hoa hpc: ^^^^^^ ^^^^^ ^^
Trang 12dm nang On luyQn thi dgi hgc 18 chuySn dg H6a hpc - Nguygn Van HSi
Bai 13:
n z n = 0,02 m o l ; n c u = 0,05 m o l if, fi m i ) j m q f ^ •
C a c h l : - ^ Or ^
N/iflM xet: X g o m hai k i m loai c6 chua Z n hoac Cu —> AgNOs he't
D o tinh k h u Z n > Cu —>• Z n phan u n g truac roi m a i den Cu X g o m Ag
Cach 2: Gpi: ncu (pu) = x m o l Bao toan electron: 2n2n + 2ncu(ph4n ijng) = "^g+
2.0,02 + 2x = 0,2a -> 0,02 + x = 0,la ,4 m ;^a;j i»«.vi
M a t khac: mx = 64(0,05 - x) + 108.0,2a = 12,08 -> x = 0,03; a = 0,5 ? (BH •
- » Dap an D
, Nhan xet: T i n h k h u Z n > Fe ->• Z n phan u n g truoc roi m a i den Fe D o mx <
mv - > Fe = 56 da phan u n g mpt phan de tao thanh C u = 64 —> Z gom
Nhan xet: Day la bai toan di|n phan d u n g djch chua nhieu chat, ca.c em nen
ap d u n g cong thuc tinh so m o l electron trao doi:
m It 2,68.4.3600 ^ , ,
n „ = — n = — = = 0,4 mol „ „
^ A F 96500
Ta c6: So'mol electron A g * nh^n vao: 0,1.1 = 0,1 m o l
-> So'mol electron Cu^* nh|n vao = 0,3 m o l
Cty TNHH MTV D W H Khang Vijt
So m o i CuS04 phan u n g = 0,15 mol. ::.,,f:-./: J.!A.f./'-:'.,-'
mcntot tang = m A g + m c u = 0,1.108 + 0,15.64 = 20,4 gam
Dap an A
Bail6: ' ' ^' -""'-^ • • umUMYl MLM ^, IsJhanxet: anlAnyH
p a y la phan l i n g dien phan hon hgp —> N e n d u n g cong thuc tfnh nhanh so' , , ^ It 1,34.2.3600 ,
- > X gom: C u C h = 0,1 m o l ; CuS04 = 0,1 m o l va K2SO4 = 0,1 m o l " ' '
T h u t u dien phan n h u sau:
C u C l 2 Cu + CI2 "-"•••"•^ ^-^^^^"'^
M o l : 0,1 0,1 0,1 m g i a m = 0,1.(64+ 71)= 13,5 gam
-> K h o i l u g n g d u n g dich con giam tie'p 17,5 -13,5 = 4 gam
cuso4 + H 2 0 - i p ^ Cu + io2 + H 2 S O 4 , *
M o l : a a 0,5a ''•TDfeMS ^ cO:dr
64a + 32.0,5a = 4 -> a = 0,05 mol ,.^14 4 r;(HO)!/
Vc,2 + V02 = (ai + 0,025).22,4 = 2,8 lit LaocJio ioinv
-» Dap a n D w i malBlHqlonyrtq [dmx • , \nnU laix w
Trang 13+ Tac dung vai nude ^
Kim loai kiem khir mxac de dang 6 nhi?t dp thvrong, giai phong k h i hidro:
2Na + 2H2O > 2NaOH + H2t
+ Tac dung v&i dung dich axit ;,
2Na + 2HC1 > 2NaCl + H2t
N e u N a d u : 2Na + 2H2O > 2NaOH + H2t
+ Tac dung vai dung dich muoi
Cho K k i m loai vao dung dich CuS04 xay ra cac phuong trinh:
2K + 2H2O > 2KOH + H2t
2KOH + CuS04 > K2SO4 + Cu(OH)2i
b Hidroxit,, „„,„.„:„.„ rfe:)|'iWomr.O.':^
+ Tac dung vdi oxit axit ;
CO2 + 2NaOH > NaiCQh + H2O
CO2 + NaOH > NaHCOa
+ Tac dung vdi dung dich muoi
Fe(N03)3 + 3NaOH > Fe(OH)3i +3NaN03
+ Tac dung vdi hap chat luang tinh
AI2O3 + 2NaOH > 2NaA102 + H2O " "
Al(OH)3 + N a O H > NaAI02 + 2H2O
c Muoi cacbonat
+ Phan ieng thuy phan (quy tim ~^ xanh; phenolphtalein ~^ hong)
do
>0
col' + H2O HCO3 +
OH-Tac dung v&i dung dich axit
Cho tu tu dung dich axit HCl vao dung djch Na2C03
Na2C03 + H C l > NaHC03 + NaCl
NaHC03 + H C l > NaCl + C 0 2 t + H2O
d Muoi hidrocacbonat
+ Tinh chat ludng tinh
NaHC03 + HCl > NaCl + C02t + H2O
NaHCOs + N a O H ^ NaiCO^ + H2O
phan img nhiet phan
2NaHC03 Na2C03 + CO2T + H2O - * •
Cty T N H H M T V DVVH Khang Vi$t
iff
IVluoi clorua
phan leng dim phan: 2NaCl * 2Na + CI2T
^ 2NaCl + 2H2O " P " " ' ' " " > 2NaOH + C h t + H2t
+ TflcdwM ^^<^2''^'*W2S04(fflc(dieuche'khiHCl) f • of 1,j NaCl (ran) + H2S04(^flc) ^ NaHS04 + H C l t
f Muoi nitrat ^
; Phan ung nhiet phan / ^ ^^^^^^^^^ , ^ j , ^ ^ , , , ,
2KN03 2KNO2 + O2 , J _^ •
+ Tinh oxi hod (khi c6 mat axit)
Cho Cu vao dung dich hon h(?p KNO3 va H2SO4 loang, Cu tan dan tao
thanh dung dich mau xanh theo phuong trinh: ^ 3Cu +2NO3 + 8H* ^ 3Cu2- + 2 N O t + 4 H 2 0
V I D U M A U • >'•' '
Vi dii 1: Hoa tan hoan toan 1,7 gam hon hop gom kim loai kiem M va oxit ciia
no vao nuoc, thu dugc 300ml dung dich chiia mQt chat tan c6 nong dp 0,2M
va 0,224 lit khi H2 (dktc) Kim loai M la ^,^^1^ j-j ^ , , ,
Mat khac: 0,02M + (2M + 16).0,02 = 1,7 M = 23 (Na) - > Dap an A
^1 du 2: Hoa tan hoan toan 1,794 gam kim loai kiem M vao 200 ml dung dich
H2SO4 0,1M Co can dung dich sau phan ung thu dugc 4,36 chat ran khan Y
Kim loai kiem M la ifiui >•
A.Rb , B K C.Na | o e D L i
Lcrigidi: , f^Q
Cac phan ung hoa hoc:
2M + H2SO4 ^ M2SO4 +H2 va M +H2O ^ M O H + ^ H 2
205
Trang 14Hoa TiQc - NQuyen van Hai
Nhdn xet: Bao toan kho'i lugng -> m y = I T I M + " ^ c o Z - + ^
V i d u 3: Hoa tan hoan toan 4,6 gam N a vao SOOjnl H2SO4 0,1M, thu dugc khi
H2 va dung dich Y Co can Y thu dugc m gam chat ran khan Gia tri ciia m la
A 11,1 B.7,1 C.14,2 D 18,2
Laigidi:
H f g a = 0-2 mol; nH2 = 0/1 mol; nH2S04 = 0,05 mol
Luu y: N a con d u se tiep tuc phan ung voi nuoc: ^^^^ ^
- N a + H2O ^ N a O H + -Hi
2 Mol: 0,1 '•^•'•'••al
2Na + H2SO4 > Na2S04 + H 2 t
Mol: 0,1 0,05 0,05
^ m = mNa2S04 + rnNaOH= 142.0,1 + 40.0,1 = 11,1 gam —> Dap an A
V i d^ 4: Cho m gam hon hgp gom N a va Ba (ti 1# mol 2:1) tac dyng voi nuoc
(du), thu dugc dung dich X va 4,48 lit H2 (dktc) Cho 300ml dung dich
Al2 (S04)3 0,2M vao X, thu dugc m gam ket tua Gia tri cua m la
A 29,54 B 6,24 C 24,86 D 9,34
Voigidi: •••M^^^' -wriq
N a + H2O > N a O H + i H 2 ^
1 Mol: 2a 2a a ' : ' : ^ ^ J '
Ba + 2H2O > Ba(OH)2 + H2 OsH O i M
Mol: a I ' : a a > h ! • ( •
= 0,2 mol -> 2a = 0,2 ^ a = 0,1 mol - aO,0 = SAc.*- •*>:•
= HNaOH + 2nBa(OH)2 = 0,2 + 2.0,1 = 0,4 mol n^^2 = aimol; n^^ = 0,2mol Q ^ ^ , Phuong trinh ion: ' ^ fef M m'jc>{ ifiol f
Mol: 0,1 0,1 0,1 - - ^ J ^ i ^ J
A13^ + 3 0 H - > Al(OH)3 4 , g r m nB/!q Di'
Mol: 0,12 0,36 0,12 , :'}H.%<3eJ4'-^^—- w(D&H + :
Hhan xet: V i Y chua hon hgp muo'i —>^ chac chan c6 chua muoi axit —>
K O H phan ung he't
" O H - ( K O H ) = ^'2' " H - i H 3 P 0 4 ) = ^ ' ^ ^ n H 2 0 = H K O H = 0,2
So do phan ling: H3PO4 + K O H > Muoi + H2O. 3 , • ,
Bao toan khoi lugng: 0,la.98 + 0,2.56 = 16,42 + 0,2.18 - > a = 0,9 y^,,, ,
Trang 15Ca'm nang fin luy$n thi dgi hpc 18 chuy§n de 116a hqc - Nguygn Van H i !
V i d\ 8: Cho day cac m u o i : K M n 0 4 , NaNCh, Cu(N03)2, CaCOs, KCIO3, AgNOs
So m u o i t r o n g day k h i nhi^t phan hoan toan t h i tao ra so m o l k h i Ion h o n so
m o l m u o i p h a n l i n g la:
A 2 B 3 C 4 ^ D 5 :d
.(••A:Ab) cp.tid IciA J;'Cd,i' Laigidi: ' i'^-^ -mddo
Nhan xet: Day l a cau h o i n h a m k i e m tra kien thiic cua hpc sinh ve d p ben
n h i | t ciia cac muo'i t r o n g c h u o n g t r i n h t u lop 10 den Idp 12
Cac p h a n ving nhiet phan:
V i d\ 9: T r p n 300ml d u n g dich X gom Ba(OH)2 0,1M va N a O H 0,1M v 6 i lOOml
d u n g d i c h Y g o m Al2(S04)3 0,1M va H2SO4 0,1M, t h u dupe a gam ket tua
G i a t r i c u a a l a ' ptj^si fMsnij! miiq-.:
Cty TNhH 1TV DWH Khang Vigt
> BaS04i 0,03
- > Dap an A ••' ;.(,{:••'• ^ 0~ ,.(y-)n'^ m.im.n
V i d\ 11: Cho 5,65 gam hon h p p X gom L i , N a va K vao 100 m l H2SO4 I M ,
thoat ra 3,92 l i t k h i H2 (dktc) v a d u n g dich Y Co can Y t h u dupe m gam chat
ran khan Gia t r i ciia m la
A 19,80 B 15,25 C 22,45 D 17,80 j
Laigidi: i ?;[
3 92
n H , = - ^ ^ — = 0,175 • ni c n III 1.,
Bao toan electron: = 2nH2 = 0,35 -> n x = = 0,35
A p d u n g d i n h luat t r u n g hoa dien: 1.0,35 = 2n 2 - + l ^ i r ^ u - ^ •
= 0,35 - 0,2 = 0,15 m o l
OH
Bao toan k h o i l u g n g :
= m x + mgQ Dap an D
in = m x +1^502- + n ^ o H - " ^'^^ ^'^"^^ 0,15.17 = 17,8 gam
209