Dien phan X voi di^n cue tro den khi bat dau c6 khi thoat ra 6 catot thi dimg dien phan, thay khoi lugng catot tang 3,2 gam va dung dich sau dien phan c6 p H bang a.. Kho'i lugng dung d
Trang 1Ca'm nang an luy^n thi d^i hgc 18 chuy6n 6i H6a hpc - Mguyjn Van Hii
X CO chxia: n^^3+ = 0,04; = 0,08; n^^^, = 0,02; Na* va SOl'
3 C u + 8 H * + 2 N O ; > 3Cu2* + 2 N O + 4 H 2 O 't:'! fh>
C u + 2Fe3* > Cu^^ + 2Fe2- s ' ' >'* '
- > = 0,03 + 0,02 = 0,05 m o l VCXQ^ = 0,05.64 = 3,2 g a m D a p an A
4 P H A N L T N G D I E N P H A N ^ l i ;+.«fcO£ *^f^.tr1-^ w.'
a L i thuyet: m,-t.,-n ; £0.0 - ,n is'ufh 6-.J / l^»d m i uO -y
* Dze« p/jflji nong chay ,
* Qua trlnh oxihoa-khie tren cdcdien cue '''^ ! i ) - , 1 , g m u
Cau t h o : A n h la A n o t n h u o n g e, E m la Catot n h a n e t h o i m a j^nntirf
A n o t - q u a t r i n h o x i hoa; Catot - qua t r i n h k h u ^ ,
A l t
* Dinh luat Faraday ( t i n h l u p n g chat t h u d u o c 6 cac d i ^ n c^rc): m = f
nF
m : kho'i l u ^ n g chat t h u duQfc 6 d i f n cvrc (gam)
A : kho'i l u g n g m o l n g u y e n t u ( m o l p h a n t u ) cua chat t h u duc^c b d i e n cure,
n: so' electron trao d o i m a i o n d a n h a n de tao t h a n h n g u y e n t u ( p h a n t u )
t u a n g u n g 6 d i | n cue |;,; '< d nfi qE<4 f
-I : c u o n g d p d o n g d i e n (ampe) t: t h a i g i a n d i ? n p h a n (giay) '
F: h l n g so Faraday (F = 96.500)
Luu y: T i r c o n g t h u c 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 e n p h a n d u g c t i n h theo cong thuc: ^ = ^
Day la cong thiec giiip gidi nhanh chong nhieu bdi todn dien phan j lii.as;? y
b V i d y mau ;• • u,*£.0 i
V i d y 1: K h i d i e n p h a n d u n g djch N a C l ( v o i d i ? n c\rc t r a , c6 m a n g n g a n xo'p)
t h i cac qua t r i n h xay ra a eye a m va cue d u o n g Ian l u g t la
A o x i hoa H2O va k h u i o n C h B k h u i o n Cl~ va oxi hoa ion Na*
Cty TNHH MTV DWH Khang Vi$t
C k h u i o n Na"^ v a o x i hoa i o n CI" D k h u H2O v a o x i h o a i o n C I " ' •* V** '"'•^
Laigidi: - '
Van d u n g cau t h o : : i ;, • '
" A n h la anot n h u o n g e - E m la catot n h a n e t h o i m a " ' >: '
N h u v a y :
Cyc a m (catot) c6 H2O v a Na* - > H2O b i d i e n p h a n :
2H2O + 2e )• H2 + 2OH- (Qudtrinhkhu) ; i r - , ; r : ,
Cue d u o n g (anot) c6 Ch va H2O Ch b i d i e n phan:
2C1- > Ch + 2e ^j^,^^^^ {Qua trinh oxi hoa) ^ , , , ,
D a p an D
V i d y 2: D i ^ n p h a n d u n g d i c h muo'i MSO4 ( v o i dien cue tro) v o i cuong d p dong
d i ? n k h o n g d o i b a n g 1,5A Sau 1351 giay t h i d u n g d i ^ n p h a n , 6 catot ehua
CO bpt k h i va kho'i l u g n g catot tang 0,672 gam Cong thuc muo'i la
d i ^ n p h a n t h a y kho'i l u g n g d u n g djch g i a m 8 g a m D e ke't tua he't l u g n g
CuS04 eon d u sau d i ^ n p h a n can d u n g 1,12 l i t H2S (dkte) G i a t r j cua C la:
Trang 2dm nang On luy^n thi dgl hpc 18 chuySn ai H6a hpc - NguySn van H5i
V i dv 4: Hoa tan 12,5 gam tinh the muoi ket tinh CuS04.nH20 vao nuac, thu
dugc 1 lit dung dich X Dien phan X (voi di^n cue tro) den khi bat dau c6
khi thoat ra 6 catot thi dimg dien phan, thay khoi lugng catot tang 3,2 gam
va dung dich sau dien phan c6 p H bang a Gia tri ciia n va a Ian lugt la
A 5 ; l B.5;2 C 3; 3 D 7; 1
Laigidi:
Phan ung dien phan: CuS04 + H2O "P^" > Cu + ^ 0 2 + H2SO4
Theo bai, dung dien phan khi 6 catot bat dau c6 khi thoat ra —> CuS04 vua
bj dien phan het (bat dau den H2O bi di^n phan)
Ta c6: m c u = 3,2 gam ^ ncu = O C U S O A = i ^ C u S 0 4 n H 2 0 = 0/05 mol ' '
61' McuS04.nH20 = ^ = 250 -> 160 + 18n = 250 ^ n = 5
ny-Dung dich sau dien phan: n^^^ - 2nH2S04 = 2ncu = 0,1 mol. ^ Q ^ ^ - J ,
^ [H^]=M = o,l = 10"^ p H = l DapanA
1 ,, snij nerf
V i du 5: Dien phan dung dich X chua 0,12 mol CuS04 va 0,04 mol NaCl (dien
cue tra, mang ngan xop) trong thoi gian 2 gio voi dong di$n c6 cuong dp la
2,68A, thu dugc V lit khi (dktc) bay ra a anot Biet hieu suat ciia qua trinh
di^n phan la 100% Gia tri ciia m la:
V i dv 6: Dien phan dung dich X gom 0,08 mol NaCl va 0,12 mol CuS04 (dien
eye tro, mang ngan xop) den khi thay thoat ra 6 anot 1,344 lit khi (dktc) thi
/ ngung dien phan Kho'i lugng dung dich sau dien phan giam di bao nhieu
gam?
A 3,48 gam B 6,04 gam C 2,56 gani D 8,60 gam ^
Cty TNHH MTV DWH Khang Vi?t
Lod gidi:
phan ling "quy doi" gia dinh: Ob^^^ v CuS04 + 2NaCl > C u C h + Na2S04 ' • J ;
Mol: 0,04 <r- 0,08 0,04 0,04 ' l i i
X gom: CuCh = 0,04 mol; CuS04 = 0,08 mol va Na2S04 = 0,04 mol
T h u tu dien phan nhu sau:
CuCh - ^ S ^ Cu + CI2 '••'^•^> ' i::;/ ^ Mol: 0,04 - > 0,04 0,04
CuS04 + H2O -^S^ C u + - O 2 + H2SO4 ••'
A oxi hoa H2O va khu ion Cu^"^ B khu H2O va oxi hoa ion Cu^*
C khu Cu2* va oxi hoa 504' -' D khu C u va oxi hoa H2O
Laigidi: + dJ'/::^':
Van dung cau tho: : > o r / r ,, ^.A ,
"Anh la anot nhuong e - E m la catot nhan e thoi ma"
+ Cue am (catot) eo Cu^* va H2O -> H2O bi dien phan: ,_tL
Cu^* + 2e > C u {Qua trinh khu)
+ Cvre duong (anot) eo H2O va ion SO4' H2O bi di?n phan:
4H2O - 4e > O 2 1 + 4H* {Qua trinh oxi hoa)
Dap an A
Vi 8: Di^n phan 1,5 lit dung dich AgNOs 0,1 M voi di^n eye tro trong t gia, cuong do dong dien khong doi 2,68A (hi^u suat qua trinh di^n phan la 100%), thu dugc chat ran X, dung dich Y va khi Z Cho 12,6 gam Fe vao Y, sau khi cac phan ung ket thiic thu dugc 14,5 gam hon hgp kim Idai va khi NO (san pham khu duy nhat eua N"*"^) Gia trj ciia t la
Phan ung di?n phan dung dich AgNOa: ;^ T ^ ,
2AgN03 + H2O > 2Ag + i 0 2 + 2HNO3 ' :
• r O ' :
-.1' -fV"': •
123
Trang 3Ca'm nang an luy$n thi djii hgc 18 chuy6n ai H6a hqc - Nguygn Van H&'\
Nhdn xet: V i cho Fe vao d u n g d i c h Y t h u d u o c h o n h o p k i m loai —> Y chiia
A g N O s —> A g N O ^ chua b i d i e n p h a n het
Cac p h a n u n g k h i cho Fe vao Y: i''"»ii'''V ^i'v :^.,.' ' 'f:^'.-']/!; ,, vv^'uvjr"'"'
Fe + 4 H N 0 3 > Fe(N03)3 + N O + 2H2O r O , y : h
M o l : 0,5a <— 2a —> 0,5a , <n • vtJuD iiTiS; X
Fe + 2Fe(N03)3 > 3Fe(N03)2 i^**"'s'^'iq''3'?:< 01 i<:
M o l : 0,25a <r- 0,5a ^ M - tOiO'
2FeC03 + -O2 FeaOs +2CO2
* Mudihidrocacbonaf' ' ' f ' i ' ^ ^ ' V 'b.i> - m b t.t : ) H liq ^x* ? V'
,0 ' ' -"f '(Ofl,* ( o i b '"•'^h r^*-' '}T('jr
, 2 N a H C 0 3 Na2C03 + CO2 + H2O , >, ,
Ca(HC03)2 — ^ CaC03 + CO2 + H2O j ^ ^ ,
* MMO? sunfua, disunfua:
,0 "• "''fidA v i j b 'Uff
4FeS2 + I I O 2 -^—^ 2Fe203 + 8SO2 , ,
.1,1 M 8,(J„A
b V I D V M A U
V i d u 1: C h e d a y cac m u o i : K M n 0 4 , N a N 0 3 , Cu(N03)2, CaCOs, KCIO3. So m u o i
t r o n g d a y k h i bj n h i ^ t p h a n tao ra so m o l k h i I o n h o n so m o l muo'i t h a m gia
p h a n l i n g la: ^
A 2 B 3 ' ' C 4 D 5 ' '
Cty TNHH MIV UVVH Khang Vi$t
Lai giai:
l^han xet: D a y la dang cau hoi li thuyet kiem tra cac em ve do ben nhi^t ciia
cac m u m v6 co C a c phuong trinh phan ling: , 5 ^ f i ^ t j i , pffifu:i :f, >
2KMn04 — K 2 M n 0 4 + M n 0 2 + O2 : to f s i i s u y i r t -n'u
i;.(f-2NaN03 — 2 N a N 0 2 + O2 ,.3, , >ttf^
Cu(N03)2 C u O +2NO2 + i o 2 n
2 CaC03 — ^ C a O + CO2
2KC103 2KC1 + 3O2 ^ , _ P
—> D a p an A
V i dv 2 (B-08): N h i e t p h a n h o a n toan 40 g a m m o t l o a i q u a n g d o l o m i t c6 Ian
tap cha't t r o s i n h ra 8,96 l i t k h i CO2 (6 dktc) Thanh p h a n p h a n t r a m ve
k h o i l u g n g ciia C a C 0 3 M g C 0 3 t r o n g loai q u a n g tren la
V i d\ 3: N u n g n o n g cac h o n h o p bot ran trong b i n h kin: C u + Cu(N03)2 (1); C u
+ KNO3 (2); Fe + S (3); MgCOs + M g (4) So t r u o n g h g p xay ra su o x i hoa
k i m l o a i la: , ; f ' | f
A 1 B 2 C 3 D 4 j ,
Cac p h u o n g t r i n h hoa hpc: ^, j |,,^ j^^,^, ^ , , (1) Cu(N03)2 C u O + 2NO2+ i o 2 ' - ;M'.;e • '• - B V
2Cu + O2 '" > 2 C u O HEoH f C u b } o x i hoa / (2) 2 K N 0 3 — ^ 2KNO2 + O2 >i
2Cu + O2 — ^ 2 C u O 3 ^ ^ C u b i o x i h o a (•^) Fe + S '" > FeS - > F e b i o x i h o a ( 4 ) M g C 0 3 — ^ M g O + CO2
M g + CO2 '" > M g O + C - > M g b i o x i hoa
- > D a p an D
125
Trang 4Ca'm nang On luy^n thi dgi hgc 18 chuy6n dg H6a hgc - NguySn Van H5i
Lieu y: 6 hon hg-p (3), Fe la chat khir —> bi oxi hoa; 6 hon hgp (4), Mg c6 the
chay trong khi CO2
V i d^ 4: Nhiet phan 18,8 gam Cu(N03)2 mot thoi gian, thu dugc 12,32 gam
chat ran Hieu suat cua phan ung nhift phan la /fiv/
Nhan xet: Khoi luong chat ran giam = khoi lugng khi bay ra
Phuong trinh hoa hoc: ^
CU(N03)2 CUO + 2NO2 + - O 2 5 ,
• Mol: X nSritt finfifli 2x 0,5x ,;t rtfik o i t tsrir)'qi
m^02 + r"02 = 18,8 - 12,32 = 6,48 gam -> 46.2x + 32.0,5x = 6,48
-> x = 0,06 mol ^ H = - ^ 1 0 0 % = 60% Dap an B
6 BAI TAP O N L U Y E N
Bai 1: Dung djch X gom Ba^ Na" (0,01 mol) va OH" (0,05 mol) Dung dich Y gom
Na^ HCO3 (0,02 mol) va CO 3' (0,01 mol) Trpn X voi Y thay tao ra m gam ket
tua Gia til cua m la
A 5,91 B.3,94 C 7,88 D 1,97
Bai 2: Hoa tan hoan toan 9,2 gam hon hop MCO3 va M'C03 vao dung dich
HCl, thu duoc V lit khi (6 dktc) va dung dich chiia 10,3 gam muoi Gia tri
cua V la
A 1,12 B 1,68 C.2,24 D 3,36
Bai 3: Cho 5,76 gam hon hop X gom muoi cacbonat va hidrocacbonat cua kim
logi kiem M tac dung het voi dung dich HCl (du), sinh ra 1,12 lit khi (0
dktc) Kim loai M la - v ^ - ^ '
A Na • B K C Rb D Li
Bai 4: Cho 14,9 gam hon hgp hot X gom Zn va Fe vao 600ml dung dich CuSO*
0,25M Sau khi cac phan ling xay ra hoan toan, thu dug-c dung dich va 15,2
gam hon hgp kim loai Y Phan tram ve khoi lugng cua Zn trong hon hgp
dau la
A 56,38% B 37,58% C 64,42% D 43,62%
Bai 5: Cho m gam hon hgp bgt Zn va Fe vao lugng du dung dich CuS04 Sau khi
ket thiic cac phan ung, Igc bo phan dung djch thu dugc m gam bgt ran
Thanh phan phan tram theo khoi lugng cua Zn trong hon hgp bgt ban dau l3
A 90,28% B 85,30% C 82,20% D 12,67%
Cty TNHH MTV DWH Khang Vigt
gai 6: Cho 5,1 gam hon hgp X gom Mg va Fe vao 250ml dung dich CuS04 0,3M
Sau khi cac phan ung xay ra hoan toan, Igc thu dugc 6,9 gam chat ran Y va dung dich Z chua hai muoi Khoi lugng cua Mg trong X la:
A 0,9 gam B 1,2 gam C 1,6 gam D 2,4gam
Bai 7 (B-07): Khi cho Cu tac dung voi dung dich chiia H 2 S O 4 loang va NaNCh, vai tro cua NaN03 trong phan ling la
A chat xiic tac B chat oxi hoa C moi truong D chat khu
Bai 8: Di?n phan dung dich X chua 0,2 mol CuS04 va 0,12 mol HCl trong thoi
gian 4 gid voi dong dien c6 cuong do la 1,34A, thu dugc m gam kim loai bam
vao catot Biet hif u suat cua qua trinh dien phan la 100% Gia tri cua m la:
A 6,4 gam B 3,2 gam C 12,8 gam D 9,6 gam
Bai 9: Di^n phan dung dich X gom 0,1 mol KCl va 0,15 mol CuS04 (di^n cue tro, mang ngan xop) den khi khoi lugng dung dich giam di 10,75 gam thi ngimg dien phan The tich khi (dktc) thoat ra 6 anot la
A 1,12 lit B 1,68 lit C 2,24 lit D 2,80 lit
Bai 10 (CD-08): Nhiet phan hoan toan 34,65 gam hon hgp X gom K N O 3 va
Cu(N03)2, thu dugc hon hgp khi Y Ti khoi cua Y so voi hidro bang 18,8
Khoi lugng ciia Cu(N03)2 trong hon hgp ban dau la
A 20,50 gam B 11,28 gam C 9,40 gam D 8,60 gam
Bai 11 (A-09): Nung 6,58 gam Cu(N03)2 trong binh kin khong chua khong khi,
sau mgt thoi gian thu dugc 4,96 gam chat rSn va hon hg-p khi X Hap thu hoan toan X vao nuoc de dugc 300ml dung dich Y Dung djch Y c6 p H bang
A 4 B 2 C 1 D 3
Bai 12 (B-08): Nung mgt hon hgp ran gom a mol FeC03 va b mol FeS2 trong binh kin chua khong khi (du) Sau khi cac phan ung ket thiic, dua binh ve nhi|t dg ban dau, thu dugc chat ran duy nhat la Fe203 va hon hgp khi Bie't
ap suat khi trong binh truoc va sau phan ung bang nhau, moi lien h$ giiia a vabla io;, A.a = 0,5b B.a = b C.a = 4b D.a = 2b
Dap an B
1 9 7
Trang 5Ca'm nang 6n luygn thi dgi hgc 18 chuy6n dg H6a hpc - Nguygn Van Hii
Bai 2:
Nhati xet: T r o n g p h a n u n g , m u o i cacbonat bien thanh m u o i clorua, nen:
i s 1 ' " o l > 2 m o l CI- - » khoi Iirong tang 71 - 60 = 11 gam ,
M2CO3 + 2HC1 > 2MC1 + CO2 + H2O IMK imfi -^oifo
MHCO3 + H C l > M C I + CO2 + H 2 0 - t - a roBSli,.^ :
N^fln xet: T i n h k h u Z n > Fe Z n phan u n g truac roi den Fe D o mx < m Y —>
Fe = 56 da phan u n g m o t phan tao thanh C u = 64 —> Y g o m Fe d u va Cu
' G p i so m o l ban dau: Z n = x; Fe = y 65x + 56y = 14,9
a m o l Fe > a m o l C u ^ k h o i l u g n g tang (64 - 56)a = 8a V « ^
Theo bai: m w n g = mv - mx = 0,3 gam -> 8a - x = 0,3
Bao toan electron: 2 n ^ 2+ = '^^zn + ^^Ve{pu) ~^ ^,15 = x + a
^ a = 0,05; x = 0,1 ^ %my„ = ^ ^ ^ 1 0 0 % = 43,62% , 0
^" 14,9 y
Bai 5: Goi so'mol ban dau: Z n = x; Fe = y N h a n thay: f
X m o l Z n > X m o l C u - » k h o i l u g n g giam (65-64)x = x I
a m o l Fe > a m o l C u -> tang (64-56)a = 8a '
Theo bai: mtang = 0 -> x = 8a
I\lhan xet: T i n h k h u M g > Fe —> M g phan l i n g truoc r o i m o i den Fe D o mx <
jnv - > Fe = 56 d a p h a n u n g m g t phan de tao thanh C u = 64 —> Z g o m
M g S 0 4 v a F e S 0 4 ^ ^ - l n r , i r ; -.^'^ :
Gpi so m o l M g ban dau = a m o l ; npg( p.) = b N h a n thay:
a m o l M g > a m o l C u kho'i l u g n g tang (64-24)a = 40a
b m o l Fe > h m o l C u -> tang (64 - 56)b = 8b
Theo bai: m t a n g = 6,9-5,1 = 1,8 gam ^ 8b + 40a = 1,8 b + 5a = 0,225
Bao toan electron: 2 n 2+ = 2nMg + 2npe(p.) -> 0,075 = a + b
_> a = 0,0375 m o l ; b = 0,0375 m o l ' ' ^ ^ ^ ^ ^ ,
- > m M g = 0,0375.24 = 0,9 (gam) Dap an A
Qua t r i n h di?n l i : NaNOs ^ + N O J H 2 S O 4 > 2H* + SO I " ' '
D u n g d i c h di§n l i c6 mat H * va N O 3 —» hoa tan Cu theo p h a n u n g :
3Cu + 2 N O : + 8 H * > 3Cu^* + 2 N O t + 4 H 2 O ^ , ' '
- > C u la chat k h u , N O J la chat oxi hoa D a p an B , i i J g n o i< > >
Nhan xet: Day la phan u n g d i ^ n phan hon hg p —> nen d u n g cong thiic tin h
M o l : 0,05 < - 0,10 0,05 0,05 -> X gom: C u C h = 0,05 m o l ; CuS04 = 0,10 m o l va K 2 S O 4 = 0,05 m o l
Trang 6elm nang On luyQn thi dgi hpc 18 chuySn dg H6a hoc - Nguyin VSn HSi
CuS04 + H2O dpdd ^ „ 1 „
> C u + - O 2 + H2SO4
^ a aSa ;
Mol: a
' ^ 64a + 32.0,5a = 4 ^ a = 0,05 mol
- > Vci2 + = (0,05 + 0,025).22,4 = 1,68 lit Dap an B
Bai 10: Phuang trinh hoa hoc: , ,
iiCL- ' , ion" Cir, r ;
Mol:
Cu(N03)2 CuO + 2NO2 + I 0 2
KNO3 — ^ KNO2 +-O2 =° ^'^S-^vd " i(.*m rifid o'X:
mart xet: Khoi lugng chat rSn giam = khol lugng k h i bay ra ^
Phirong trinh hoa hpc: '' '^ymii fmf'Mttml t « MiirM
CU(N03)2 CuO + 2NO2 + -O2
Cty TNHH MTV DWH Khang Vi$t
l i X H CHAT CIJA CAC OXIT Ml
OXIT BAZO + AXIT
a- * i^ififel I <jn/ri ' t ' / I ,' } i i W i t ' • •
* phan ung trao aoi 1 L
:'.i.ih 'itn.ih tfrti ' •
AI2O3 + 6HC1 > 2 A I C I 3 + 3H2O
CuO + H2SO4 > CuS04 + H2O Fe203 + 6HNO3 > 2Fe(N03)3 + 3H2O
» Phan ung oxi hoa-khu ->gfti^O??^P'-fv'iv *n'Mvni,» 'J 4 if,,
3FeO+ IOHNO3 > 3Fe(N03)3 + N O + 5H2O „ i j , , , Fe304 + IOHNO3 > 3Fe(N03)3 + N O 2 + 5H2O v ' • • i 2FeO+ 4H2S04(^flc) > Fe2(S04)3 + SO2 + 4H2O ' ' '
Dap a n C
Vi du 2: Hoa tan hoan toan 5,44 gam hon hop X gom Fe203, FeO, CuO can 80
m l axit H2SO4 I M (loang) K h u hoan toan 5,44 gam X bang khi H2 (nung nong) thu dugc m gam kim loai Gia tri cua m la
Trang 7Ccim nang On luygn thi dgi hpc 18 chuySn ai H6a hpc - Nguygn VSn Hii
V i 3: H o a tan het 20,88 gam m o t oxit sat bang d u n g d i c h H2SO4 dSc, nong
(du), t h u dugc d u n g dich X va 1,008 h't k h i SQz (san p h a m k h u d u y nhat, 6
dktc) Co can d u n g dich X, thu dugc m gam muoi sunfat khan Gia t r i o i a m la
A 36 B.24 C 72 D 54
Lcngidi: ' ^ ' 1 - - i'-OlAm i K, Nhan xet: O x i t sat FexOy tac d u n g v o i H2SO4 dac, non g SO2 t h i oxit la
FeO hoac Fe304
Cac ban l u u y rang 1 m o l FeO hoac Fe304 deu chiia 1 m o l Fe^^ nen deu c6
kha nang n h u o n g 1 m o l electron, do do:
V i d u 4: Hoa tan hoan toan m gam Fe^Oy bang H 2 S O 4 dac nong, t h u d u g c dung
dich chiia 12 g a m m g t loai m u o i sat d u y nhat va 0,224 l i t SO2 (dktc) Cong
i thijrc cua oxit sat va gia t r i m Ian l u g t la , ,
Nhqn xet: O x i t sat FexOy tac d u n g v o i H2SO4 dac, n o n g - > SO2 t h i oxit la
FeO hoac Fe304
Trong 1 m o l FeO hoac Fe304 deu chua 1 m o l Fe^* n e n d e u c6 k h a nang
Cty TMHH MTV DWH Khang ViQt
y i 5: H o a tan hoan toan 10,56 gam hon h g p bgt Fe304 v a C u t r o n g 160 m l
d u n g d i c h H2SO4 I M (loang, v u a du) Sau k h i cac p h a n u n g xay ra hoan
toan, t h u d u g c d u n g d i c h X Co can X t h u dugc m g a m muo'i khan Gia t r j cua m la « > •
A 15,36 , 1 B 23,36 C 17,28 D 13,28. MI,
Laigidi: j i a!
Gpi so m o l : Fe304 = a; C u = b Theo bai: 232a + 64b = 10,56
Nhqn xet: C h i c6 Fe304 phan u n g true tiep v o i axit Cac p h a n u n g hoa hgc:
V i 6: C h o 3,5 g a m h o n h g p X g o m A l , Fe v a C u 6 dang b g t tac d u n g hoan toan v o i O2 t h u d u g c h o n h g p Y g o m cac oxit c6 k h o i l u g n g 4,46 gam The tich d u n g dich H 2 S O 4 I M vira d u de phan u n g het v o i Y la
C u O + H2 — ^ C u + H2O
lim y: K h i CO, H2 chi k h u dugc cac oxit ciia k i m loai tir Z n ve sau
Tac dung oai Al (nhiet nhom)
2A1 + Fe203 — ^ A I 2 O 3 + 2Fe ' 1/;) J' "
-133
Trang 8Cim nang 6n luygn thi dgi hgc 18 chuygn dg H6a hgc - Nguygn Van HSi
'** 8A1 + 3Fe304 — 4 A I 2 O 3 + 9Fe
Cty Ti\ : '/ITV DVVH Khang Vi?t
14 3CuO -> A I 2 O 3 + 3Cu
A I 2 O 3 + 2Cr
2A1 + Cr203
-V i d\ 1 (A-09): Cho l u o n g k h i C O (du) d i qua %1 g a m h o n h g p g o m C u O va
A I 2 O 3 n u n g nong den k h i phan u n g hoan toan, t h u dugc 8,3 g a m chat ran
Kho'i l u g n g C u O c6 trong hon hgp ban dau la:
A 0,8 gam B 8,3 gam C 2,0 gam D 4,0 gam
, -!,.•., ' V' - '• Lbigiai:
Nhan xet: K h i C O chi k h u dugc CuO theo phan u n g : i f • I'lKG t, <
C u O + C O Cu + CO2
T a n g - g i a m k h o i l u g n g : m o (trong CuO) = 9 , 1 - 8 , 3 = 0,8 g a m SO.O :!o
y n o = ~ = 0,05mol > n^uo = 0,05 mol meg e,fl o t O *
» ncuo =0/05.80 = 4 , O g a m > D a p an D ^ ' ^
V i d u 3: D a n luong k h i C O d i qua h o n h g p g o m C u O v a Fe203 nung
nong, sau m o t thoi gian t h u dugc chat ran X va k h i Y C h o Y hap thu
hoan toan vao d u n g dich Ca(OH)2 d u , t h u dugc 7,5 g a m ket tua Chat
'! ran X phan l i n g v o i d u n g djch H N O 3 d u thu dugc V l i t k h i N O (san pham
k h u d u y nhat, 0 dktc) Gia t r i ciia V la
Nhqn xet: K h i cho hon hgp oxit tac dung v o i k h i C O thi:
H e traodcS = 2nQQ. M a I\QQ = TXQQ^ = 0,075 mol traodoi = 0,15 mol
Bao toan electron:
ttg trao doi — 3 n jvjo ' ^ N O ~ 0,05 mol >
- > V N O = 1,12 lit -> Dap an C. f
-V i d v 2: C h o k h i C O (du) tac d y n g v o i h o n h g p X g o m A I 2 O 3 , FezOa, C u O
thu dugc chat ran Y Cho Y vao d u n g djch N a O H (du), khuay k i , tha'y con
lai phan khong tan Z Phan khong tan Z g o m
; A A I 2 O 3 , Fe, C u B Fe203,Cu C A l , Fe, C u D Fe, C u r
K h i cho Y tac d u n g v o i N a O H d u t h i AI2O3 b i hoa tan hoan toan:
AI2O3 + 2 N a O H > 2 N a A 1 0 2 + H 2 O
Vay Z gom: Fe, C u Dap an D " • '
V i 3: K h u hoan toan m g t oxit sat FexOy 6 n h i f t d g cao can vira d u V lit k h i
CO (dktc), sau phan u n g t h u dugc 0,84 g a m Fe v a 0,02 m o l k h i CO2 Cong
thiic ciia oxit sat va gia t r i ciia V la
A Fe304 va 0,224 B Fe304 va 0,448 ^ ^ ' l '
C FeO va 0,224 D Fe203 va 0,448 ;n ;
Lai gidi:
Cach 1 : Giai theo p h u o n g t r i n h hoa hgc
FexOy + y C O — ^ xFe + y C 0 2
M o l : a ax ay 0,84
d u h o n h g p ran g o m FeO va Fe304 n u n g nong Sau k h i cac phan u n g xay "
hoan toan, khoi l u g n g hon hgp ran giam 4,0 gam Gia t r i ciia V !a
135j
Trang 9dm nang On luy$n thi djii h(?c 18 chuy6n d6 H6a hqc - Nguygn Van Hil
V i dv 5: Cho 6,72 lit khi C O (dktc) di tu tir qua ong su nung nong dung 10,44
gam mpt oxit sat den khi phan ung xay ra hoan toan, thu duoc hon hgp khi
Y CO ti khoi so vai hidro bang 18,8 Cong thiic cua oxit sat va phan tram the
tich cua khi CO2 trong Y la - t - u.j' >
A F e O ; 2 8 % B Fe203; 72% C Fe203; 28% D Fe304; 72%
V i dv 6 (CD-09): De dieu che dug-c 78 gam C r tu Cr203 (du) bang phuong
phap nhi^t nhom voi hi^u suat cua phan ung la 90% thi can toi thieu m gam
V i dv 7: Nung hon hgp bpt gom 6,96 gam Fe304 va m gam A l a nhi^t d^ cao
Sau khi phan ung hoan toan, thu du(?c 9,66 gam hon hgp tin X Cho X
phan ling voi axit H2SO4 (loang, du) thoat ra V lit khi H2 (dktc) Gia trj cua
L u u y rang, trong phan ling nhi|t nhom, thuong ap dyng djnh lu|t bao toan
khoi lugng, cu the:
i"Fe203 + mAi = m x - » m^i= 9,66 - 6,96 = 2,7gam ^ nAi= 0,1 mol
Phuong trinh phan ung: 3Fe304 + 8A1 > 9Fe + 4Ah03
Mol: 0,03 0,08 0,09 0,04
Cty TNHH MTV DVVH Khang Vi^t
Kim loai sau phan ung gom: A l = 0,02 mol; Fe = 0,09 mol
3,
jChi tac dung voi axit: A l -> - H 2 va Fe -> H2 _> nH2 = 0,12 m o l - > V H 2 = 2,688 lit ^ - D a p a n B ' '
V i dv 8: Nung nong 48,2 gam h6n hgp gom A l va Fe203 (trong dieu ki?n
khong CO khong khi) den khi phan ung xay ra hoan toan Chia hon hgp thu dugc sau phan ung thanh hai phan bang nhau Phan mot phan ung vira dii voi 150 ml dung dich N a O H 2M De hoa tan het phan hai can vua dii dung dich chua a mol H C l Gia tri cua a la
A 0,9 B 1,3 C.0,5 D.1,5
n N a O H = 0,3.1 = 0,3 mol
Nhan xet: Khi cho phan 1 + dung dich N a O H , tat ca A l va AI2O3 deu tac
d y n g va chuyen thanh NaA102
Do vay, bao toan nguyen to'Al, ta c6: n A i = nfsjaOH = 0,3 mol
48,2-0,6.27 ,
" F e z0 3 = = 0,2 mol Ban dau: nAi = 2.0,3 = 0,6 mol
160 Fe203
Mol: 0,2 •
2A1 0,4
AI2O3 + 2Fe 1.0 0'2 0,4
Cac chat trong phan 2: nAi = 0,1 mol; nFe= 0,2 mol; nAi203 = 0,1 mol nHci =3nAi +2nFe+6nAi203 = l , 3 m o l
- » Dap an B
2 O X I T L I / O N G T I N H
a L i thuyet:
Cac oxit luong tinh thuong gap: ZnO, AI2O3
'< Tac dung voi axit
J ah qsQ' <f
^Al203 + 6HC1 IznO + H2SO4
> 2A1C13 + 3H2O -> ZnS04 + H2O
-V i d^ 1: C h i diing dung dich K O H de phan bi^t dugc cac chat rieng bi?t trong
nhom nao sau day?
A A l 2 0 3 , A L B K , N a C Zn, A l D Fe, Mg
Laigidi:
Loai B: K, Na deu tac dung vai H2O trong dung djch K O H va sui bgt khi
^r^7
Trang 10Ca'm nang 6n luy^n thi d^i hgc 18 chuy§n dg H6a hgc - Nguyln Van Hai
Loai C : Zn, A l deu tan trong dung dich K O H va siii bpt khi
Loai D: Fe, M g deu khong tac dung voi dung dich K O H
—>• Dap ?n A Hien tugng nhu sau:
, AhOstan: Jv b r a S 1,0- <
A I 2 O 3 + 2 K O H > 2KAIO2 + H2O m.^abn'iiM -'ii
l^^^^M tan va sui bpt k h i : , • ^ , ,,5,:.,,,,
^»rr A l + K O H + H2O > KAIO2 + | H 2 t ^J®^' " •
V i d\ 2: Hoa tan hoan toan m gam hon hop X gom Na20 va AI2O3 vao H2O thu
dugc 200ml dung dich Y chi chua chat tan duy nhat c6 nong do 0,5M Thoi
khi CO2 (du) vao Y thu dugc a gam ket tiia Gia tri cua m va a Ian lugt la
Thoi khi CO2: NaA102 + CO2 + 2H2O > Al(OH)3 + N a H C 0 3 " '
Mol: 0,1 0,1
^ a = mAi(OH)3 = 0,1.78 = 7,8 gam; * ' '>'^ ' «
va m = m N a o + mAbO-, = 0,05.62 + 0,05.102 = 8,2 gam ' s*^"^'^ *
—> Dap an D
V i d\ 3: Cho khi H2 (du) di vao 6'ng s u nung nong dvrng hon hgp X gom
AI2O3, FezOs, C u O thu dugc chat ran Y Cho Y vao dung dich K O H (du),
khuay ki, thay con lai phan khong tan Z Phan khong tan Z gom ^
A AI2O3, Fe, C u B Fe203,Cu C Fe, C u D A l , Fe, (fu
' Ldigiai: '
Lieu y: K h i H2 khong k h u dugc AI2O3 nen xay ra 2 phan ung:
- > Chat ran Y gom: Fe, C u , AI2O3
K h i cho y tac dung voi K O H d u thi AI2O3 bi hoa tan hoan toan do c6 tinh
luong tinh:
AI2O3 + 2 K O H > 2KAIO2 + H2O
Vay Z gom: Fe, C u —> Dap an C
y i 4: C h o 6,63 gam hon hop gom BaO va AI2O3 (ti 1§ mol 3:2) vao nude (du), thu duoc dung djch X Dung dich Y gom H C l 0,3M va H2SO4 0,2M Cho tu
tu den het 100ml dung dich Y vao X, thu dugc m gam ket tiia Gia tri ciia m
Mol: 0,02 - > 0,02 0,02 \^i\
Al(OH)3 + 3H* > A P - + 3H20'^'''^ " ' ' Mol: 0,01 < - 0,03 ^ H*-^^''' •+ '
)2- ^ BaSOii
Ba2^ + S O 4 "
Mol: a02 <-0,02 a02 • ' H '
- > m = mAi(OH)3 + mBaso4 = 0,01.78 + 0,02.233 = 5,44 gam
Trang 11dm nang On luygn thi dgi hqc 18 chuy6n 66 H6a hpc - Nguyjn Van Hi\
Nhan xet: Dung dich X trong suo't AbOa tan het
NaOH + HCl > NaCl + H2O
Mol: 0,1 <- ai rt .-v;f;Vijt!^-•
NaA102 + HCl + H2O > Al(OH)3>l' + NaCl
Mol: 0,1 0,1 ' '
-> a = 0,1.78 = 7,8 gam —> Loai phuang an A ua C
Nhan thay: Khi cho 400ml dung dich HCl vao X, toan bp NaA102 se chuye'n
het thanh ket tiia Al(OH)3, va sau do bi hoa tan mot phan trong HCl:
NaAlCh + HCl + H2O > Al(OH)3^ + NaCl
Al(OH)3 + 3HC1 > AICI3 + 3H2O
0 3 — X
Ta c6: nAi(OH)3 " mol -> x - — = 0,1 ^ x = 0,15 mol >•
Tu day suy ra ban dau: Na = 0,25 mol; AI2O3 = 0,075 mol
^ m = 0,25.23 + 0,075.102 = 13,4 gam Dap an A ; + HO
4 OXIT AXIT
a Li thuyet
* Tdc dutiQ vai baza
CO2 + 2NaOH > Na2C03 + H2O
CO2 + NaOH > NaHC03
CO2 + Ca(OH)2 > C a C O s I + H2O ,
2CO2 + Ca(OH)2 > Ca(HC03)2
* Phan ieng oxi hoa-khu
SO2 + Br2 + H2O > H 2 S O 4 + 2HBr
b V i m l u
Vi d^ 1: Cho day cac oxit: NO2, Cr203, SO2, CrOs, CO2, P2O5, CI2O7, Si02,
CuO Co bao nhieu oxit trong day tac dyng dup-c voi dung djch NaOH
loang?
A 7 B 8 C 6 D.5
li Laigidi:
Nhan xet: Day la cau hoi kha tong hop ve tat ca cac loai oxit Luu y them:
Cac oxit Si02, CuO khong tac dyng voi dung djch NaOH loang
Cac phan ung hoa hpc aia cac oxit voi dung dich NaOH loang (du):
NO2 + 2NaOH > NaN02 + NaNOs + H2O
Cr203 + 2NaOH — - > 2NaCr02 + H2O
.14-.c
Cty TNHH MTV DWH Khang Vijt
sc
Cr
SO2 + 2NaOH > Na2S03+ H2O
Cr03 + 2NaOH > Na2Cr04 + H2O - f : ^
r 0 2 + 2NaOH > Na2C03+H20 ^ > , ! i O ^ '
C I 2 O 7 + 2NaOH > 2NaC104 + H2O f^,/>- ^tini.>>;^ ^
—> Dap an A n ^ - w n n < • r i < ,r a • ikrlt it'z-w
Vi du 2 (CD-09): De phan biet CO2 va SO2 c6 the dung thuoc thu la
A Dung djch Ba(OH)2 B CaO "''' '
C Dung dich NaOH D Nuacbrom * ' *
Lot gtat:
Nhan xet: Khi CO2 va SO2 deu c6 tinh axit, tuy nhien khi SO2 con c6 tinh khu
- > CO the lam mat mau nuoc brom: s
SO2 + Br2 + 2H2O > H2SO4 + 2HBr ]
—> Dap an D g n o i
Vi dy 3: Hap thu het V ml khi SO2 (dktc) vao nuoc brom du, thu dugc dung
dich X Them dung dich BaCh du vao X, thu dugc 2,33 gam ket tiia Gia tri ciia V la
A 112 B 224 C 560 D 336
Laigidi:
2 33
n B a S 0 4 = - ^ =0,01 mol
SO2 + 2Br2 + 2H2O > H2SO4 + 4HBr
H 2 S O 4 + BaCb > BaSOd + 2HCI • - i ,
-> nso, = ngaSOA = O'Ol mol -> V = 0,01.22,4 = 0,224 lit = 224ml
-> Dap an B
Vi dy 4: Hap thu hoan toan 336ml khi CO2 (dktc) vao 1 lit dung dich Ca(0H)2
0,01M, thu dugc dung dich X va m gam ket tiia Gia tri cua m la
A 1,0 B.1,5 C.2,0 D.0,5
nco2 = ^ = 0,015 mol; n ^ ^ = 2nc,(OH)2 = 2.1.0,01 = 0,02 mol ^ ,
a = - S H I = -2l£2 ^ 33 _^ tao 2 loai muoi: Cacbonat va hidrocacbonat
nco, 0,015 Cach 1: Giai theo phuang trinh phan ung
CO2 + Ca(OH)2 — — > CaCOsi + H2O
J ^ ^ ^ 141
Trang 12Y g o m : Na^ = 0,02 m o l ; = 0,02 m o l ; C O = 0,01 m o l ; H C O i = 0,02 m o l
Bao t o a n k h o i l u g n g : a = m + + m + + m 2- + rn
Na K 3 HCO3
= 0,02.23 + 0,02.39 + 0,01.60 + 0,02.61 , , , ->• m = 3,06 g a m -> Dap an B ^ ,,
V i d^ 6: Cho 0,1 mol P2O5 v a o 400ml d u n g d i c h K O H 2M Sau k h i phan l i n g
x a y ra h o a n t o a n , d u n g d i c h t h u d u g c c6 cac c h a t la
f A K3PO4 v a K2HPO4 B K2HPO4, KH2PO4
:\ K3PO4 va K O H D H3PO4 va KH2PO4
Lcngidi:
Nhanxet: P2O3 + 3H2O > 2H3PO4 n H 3 P 0 4 = 2 n p 2 0 5 = 0,2 m o l
- > = = 4 > 3 ^ K O H d u va tao ra muoi K3PO4
5, BAI T A P O N L U Y E N Bai 1: E)6't 4,2 gam Fe trong khi oxi, thu dugc hon hgp X gom FeO, Fe203, Fe304 Cho X tac dung voi dung dich HNO3 loang (du), thu dugc khi N O (san pham k h u duy nhat) va dung dich chua m gam muoi Gia tri ciia m la
A 12,10 B 18,15 C.24,2 D 20,57
Bai 2: Hon hgp X gom C u O va Fe203 Hoa tan hoan toan 16 gam X bang dung dich H2SO4, thu dugc 36 gam muo'i Mat khac, neu khu het 16 gam X bang
C O (du), dan hon hgp khi thu dugc vao dung dich Ca(OH)2 (du), tao thanh
m gam ket tiia Gia tri cua m la
A 10 B 15 C 2 5 D 2 0 Bai 3: Hon hgp X gom MgO, Fe203 va C u O Hoa tan het 9,6 gam X bang dung djch H2SO4 (du), thu dugc dung dich chua 22,4 gam muoi Mat khac, neu khu hoan toan 9,6 gam X bang CO (du), cho hon hgp khi thu dugc Igi tu tu qua dung dich Ca(OH)2 (du) thi thu dugc m gam ket tua Gia tri ciia m la :
A 16 B.20 C 12 D 2 4 Bai 4: Cho V lit khi C O (dktc) tac dung het voi 10 gam Fe203 nung nong, thu dugc hon hgp X gom FeO, Fe203 va Fe304 Cho X tac dyng voi dung dich
HNO3 du, thu dugc 1,12 lit NO (san pham khu duy nhat ciia N*^ a dktc)
Gia tri ciia V la
A 1,68 B.2,24 C 3,36 D 4,48
Bai 5 (B-12): Dan luong khi C O di qua hon hgp gom C u O va Fe203 nung nong, sau mot thoi gian thu dugc chat ran X va khi Y Cho Y hap thu hoan toan vao dung dich Ba(0H)2 du, thu dugc 29,55 gam ket tiia Chat ran X phan ling voi dung dich HNO3 d u thu dugc V lit khi N O (san pham khu duy nhat, 0 dktc) Gia tri ciia V la
A 2,24 B.4,48 C 6,72 D 3,36
Sai 6 (B-10): K h u hoan toan m gam oxit MxOy can vira dii 17,92 lit khi C O (<Jktc), thu dugc a gam kim loai M Hoa tan het a gam M bang dung dich H2SO4 dac nong (du), thu dugc 20,16 lit khi SO2 (san pham k h u duy nhat, 6
<Jktc) Oxit MxOy la , ,,, ,
A FeO B C r O C Cr203 D Fe304
143
Trang 13calm nang On luyjn thi d^i hgc 18 chuy6n 6i H6a hgc - Nguygn Van HSi
Bai 7: Syc 4,48 lit khi CO2 (dktc) vao 1 h't dung dich X chiia hon hp-p
Ba(OH)2 0,05M va NaOH 0,2M Sau khi cac phan ung xay ra hoan toan thu
dug-c m gam ket tiia Gia tri ciia m la
A 19,70 B.9,85 C 11,82 D 15,76
Bai 8 (CD-12): Cho 1,42 gam P2O5 tac dung hoan toan vol 50nJ dung dich
KOH IM, thu duQ-c dung dich X Co can dung dich X thu dug-c chat ran khan
gom <' '
A K3PO4 va KOH 'P'-^ ^ B K2HPO4 va K3PO4
C KH2PO4 va K2HPO4 D H3PO4 va KH2PO4
Bai 9: Dan luong khi C O di qua hon hgp gom CuO va Fe203 nung nong,
sau mot thoi gian thu dugc chat ran X va khi Y Cho Y hap thu hoan toan
vao dung djch Ba(OH)2 du, thu dugc 11,82 gam ket tua Chat ran X phan
ling vai dung dich HNO3 du thu dugc V lit khi NO (san pham khu day
nhat, 6 dktc) Gia tri ciia V la
A 1,120 • B 2,016 C 0,896 D 1,344
Bai 10: Hoa tan hoan toan 8,16 gam hSn hgp gom Fe304 va FeS2 trong dung
dich axit HNO3 (dac, du), thu dugc 4,032 lit khi NO2 (dktc) va dung dich X
Cho X tac dung voi dung djch Ba(OH)2 du, Igc ket tua va nung trong khong
khi den khoi lugng khong doi thu dugc m gam chat ran Gia tri ciia m la
A 16,18 B 15,86 C 12,66 D 30,26
Bail: nFe = 0,075 mol ^ ^ ^ , , , ^ ^.^
Nhan xet: Bai nay neu dua theo phuong trinh phan ung se ra't ciai dong va ton
nhieu thai gian
O day, cac em can su dung so do phan ung:
Fe > X (FeO, Fe203, Fe304) '""^"^ > Fe(Na)3
«'P Fe > Fe(N03)3 ff,tt^-r'iih '^.P ^ I K ' '
Mol: 0,075 0,075 ricr
-> m = 0,075.242 = 18,15 gam -> Dap an B
Bai 2:
Nhan xet: Khi cho X + H2SO4 thi oxit chuyen thanh muoi sunfat va m<?^
nguyen tu O^" trong oxit dugc thay the bang mgt ion SO 4
Tang giam khoi lugng: '
1 mol 0 2 - > 1 mol SO 4" Khoi lugng tang 96 - 16 = 80 gam '^^
a mol <- tang 36 -16 = 20 gam
Cty TIMHH MTV DWH Khang Vijt
20 _^ a= — =0,25 mol no (x) = 0,2 mol
80
Khi cho 16 gam X tac dyng vai CO thi: no (x) = n c o 2 = "CaCOs = 0,2 mol
m =0,2.100 = 20 gam ^ DapanD. , „ K n : r i « o : , „ f
Bai3:
Nhan xet: Khi cho X + H2SO4 thi oxit chuyen thanh muoi sunfat va mgt
nguyen tii 0^~ trong oxit dugc thay the bang mgt ion SO l~
1 mol 0 2 - > 1 mol SO 4 ' -> Khoi lugng tang 96 - 1 6 = 80 gam
a mol <r- tang 22,4-9,6 = 12,8 gam
12 8
-> a=—^=0,16 mol -> no(X) = 0,16 mol : '
Ltfu y: Khi cho X tac dung vai CO thi: no (X) = nco2 = " C a C 0 3 '( ''''^ ' '
- > ncaC03 = 0,16 mol
- » m = 0,16.100 = 16 gam -)> Dap an C c O * - - ^ - • - m , : Y S A Bai 4: , •
" 22^4 " 'I r.O-S.0 • €.0 -,,f0(1 - f r - 5 n :finfirin j ' :,
+3 +3
So do phan ling: FezOg > X """^"^ > Fe(N03 )3 + NO
Nhan xet: So oxi hoa ciia Fe 6 san pham cuoi cimg hoan toan giohg vai ban
dau ' ^' -"^^ '
lAc dau C O nhuong electron cho Fe203 > X, sau do X nhuong so
electron vua nhan dugc cho N"^^ de tra thanh Fe(in)
2nco = 3r »NO "co = 0'075 mol -> V = 1,68 lit Dap an A
Pe2 0 3 , C u O > X ^"^"^3 ) Fe(N03)3 + Cu(N03)2 ^ NO
N/ian xet; So' oxi hoa ciia Fe va Cu a san pham cuoi ciing hoan toan giong
voi ban dau
^_ f , ,,,, ,
Luc dau CO nhuang electron cho Fe203, CuO > X, sau do X nhuong so' electron vua nhan dugc cho N'^ de tra thanh Fe(III), Cu(II)
2nco =3nNo - > nNO = 0,lmol V = 2,24lit md<.>SvO- , ,
Trang 14Ca'm nang On luy^n thi dgi hpc 18 chuyen 66 H6a hqc - Nguyjn Van Hi)
Bai6:
nco =0/8 mol; nso2 =0/9 mol
Nhan xet: Vi oxit MvOy bj khu boi khi C O -> Logi B va C vi C O khong khir
dugc oxit ciia crom
O cac phuong an con lai, M deu la Fe —> M la Fe
Ta co: no (oxit) = nco = 0,8 mol »
Bao toan electron: 3npe = 2nso2 = 0,6 mol ' " '"' 'v^
-> i}F^ = M = l ^ OxitsatlaFe304 DapanD
no 0,8 4
Bai7:
" O H - = " " N a O H + 2nB3(OH)2 = 0,2 + 2.0,05 = 0,3 mol Trong Z: O H '
n„ 2+ = 0,05 mol; n^, + = 0,2 mol
Ba Na Nh^n thay: ° " = — = 1,5 > 1 -> Phan ling t?o ra 2 muoi cacbonat va
nc02 a2 ^ , : ^^^
hidrocacbonat
Tinh nhanh: n^^2- = "QJ^- - "002 = 0,3 - 0,2 = 0,1 mol!
3 -> Nhan thay: n^^2^ < n^^2- n B a C O a = "332+ = 0,05 mol
3 ->m = a05.197 = 9,85gam^ DapanB
CO2 + Ba(OH)2 > B a C a + H2O , '
% Mol: a06 a06
,, Nhan xet: Khi cho hon hgp oxit tac dyng voi khi CO thi:
n g trao doi = 2nco • Ma n^o = " 0 0 2 ~ ^'^^ ^'^^ ~^ = 0,12 mol
Bao toan electron: n g t r a o d 6 i = 3 n]sjo-> nj^o 0,04 mol
^ V N o = a 8 9 6 1 i t I
-» Dap an C
Cty TNHH MTV DVVH Khang Vigt
1 i w Gpi so mol: Fe304 (a mol) va FeSz (b mol) Ta c6:232a + 120b = 8,16
Cac phan ung khu: • * Fe304-le >3Fe^3 ^ j„
FeS2-15e > ¥e*^ + 2S^ ':;•.; > !>
Bao toan lectron: , 1 , , , 1/0", u i i ; i i j i i <
n N 0 2 = " F e 3 0 4 + 1 5 n F e S 2 s f U w ' E K * ! i ,1 ti
a + 15b = 0,18 a =0,03; b = 0,01 • ' ; Bao toan nguyen to'Fe va S: > ) 1 1 ' '> fj||.ii[| ' 4 , , , , , Fe304 >• -Fe203 ' ' wsV; Vvh f M i s - P •
2 f J'fl * f fi.jt.'i IM *- - Hi: J
Mol: a03 a045
FeS2 > -Fe203 + 2BaSa
Trang 15elm nang 6n luy^n thi dgi hgc 18 chuySn dg H6a hpc - Nguyjn Van H5i
* Tdc dung v&i dung dich kiem c ^ ^.^ ^
CI2 + 2 K O H > K C l + K C I O + H 2 O {Nu&c Gia-ven)
3Cl2 + 6 K O H > 5KC1 + KCIO3 + 3H2O
CI2 + Ca(OH)2 {sua voi) > C a O C h + H 2 O {Clorua voi)
* "Day" halogen ditngsau
CI2 + 2NaBr > 2NaCl + Br2 '! + 5.(X0.Ooi a i ,
Br2 + 2NaI > 2NaBr + I2 D n ! 5 q M <
* Tdc dung vai hap chat
CI2 + 2FeCl2 >• 2FeCl3 * ' '-IdSwiv.}, - ;
V i di^ 1: Phat bleu nao sau day la sai? t' » > < , t^^ n
A Halogen la nhung chat oxi hoa manh
B Kha nang oxi hoa cua halogen giam tir flo den iot :
C Cac halogen deu c6 the c6 so oxi hoa : -1, +1, +3, +5, +7
D Cac halogen c6 tinh chat hoa hpc tuong t\ nhau
LMgidi:
Nhan xet: Do flo la nguyen to'co dp am di^n manh nhat -> flo chi the hi§n so
oxi hoa -1 trong cac hop chat Phuong an C sai
-> Dap a n C
V i d\ 2: Cho biet cac phan ung xay ra sau: ' ' i i
2FeBr2 + Br2 >• FeBra • ^ (1) ,
2NaBr + C h > 2NaCl + Br2 (2)
Cty TNHH M T V DVVH Khang Vigt
phat bieu diing la:
A CI" CO tinh khu manh han B r B Br2 c6 tinh oxi hoa manh hon CI2
Q B r CO tinh khu manh han Fe^* D CI2 c6 tinh oxi hoa hon Fe^*
Laigiai: i ijof* \is ri\
t^han xet: (1) —>• Tinh oxi hoa Br2 > Fe'^; tinh k h u Fe^* > Br" •() li / : ; \
(2) Tinh oxi hoa CI2 > Br2; tinh khu Br- > CI", tinh oxi hoa CI2 > Br2 > Fe^*; tinh khu Fe^* > B r > Ch <i / d i , , '
• — ^ D a p a n D tiHf <V: ('» rii/l:
Vi dv 3: Chpn nhan dinh dung Cac halogen deu c6 tinh cha't chung la
A Chat khi 6 dieu kien thuong
B Co tinh oxi hoa ^^nub wb gnv/ui i o v g m i iCfiq
C V u a CO tinh oxi hoa, vira c6 tinh khtr n wMrt d 9 IdA gm-ml t-n uh' !
D Tac dung manh voi nuoc , V|SOnM S tOnlV' f ,
I Laigiai:
Lo^i A vi F2, CI2 la cha't khi; Br2 la chat long va I2 la chat ran ffj (jjyC'j Loai C vi F2 chi c6 tinh oxi hoa, khong c6 tinh khu ^ ^ Loai D v i CI2, Br2,12 deu it tac dung voi nuoc
(1) Cho dinh sat vao dung djch H2SO4 {loang, nguoi); ,^
(2) Sue khi SO2 vao nuoc brom; " (3) Cho nuoc brom vao dung dich Nal; ' -C>C
(4) Cho la A l vao dung dich H2SO4 (dac, ngupi) ^ nV,t >tsit:'
So' thi nghi?m xay ra phan ung oxi hoa-khu la Q,,| j r ^ '! , (|/;
A-2- B I c 3 • \ : , p , 4
LMgidi:
Cac phan ung hoa hpc a cac thi nghi^m:
0 ) Fe + H2SO4 (loang, ngupi) > FeS04 + H 2 t ^ ''• ' (2) S02 + Br2 + 2H2O > H2SO4 + 2HBr * ' ' ' "
(3) Br2 + 2NaI > 2NaBr + I2 - * ~ ' ' '
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