+ M a u lam quy tim hoa do la H C l va H2SO4.
+ Mixu Ihm quy tim hoa xanh la NaOH.
+ Hai mau khong Ic^m doi mau quy tim la K C l vii BaCb.
- Cho mot trong hai mau lam quy tim hoa do vao hin liTtft hai dung djch m u o i :
+ Dung djch H C l khong tac dung difdc \6i hai mu6'ị
+ Dung dich H2SO4 tao ket tua triCng vdi BaClj con vdi K C l thi khong hien
tircJng.
Phan dgng va phiiong ph^p oi5i H6a hpc 11 VP cO - D5 XuSn Hang
B A I T A P A P D g N G
Bai 1. Viet phufdng trlnh ion rut gon cua cac phan iJng (neu c6) xay ra trong dung djch giiJa cac c$p chaít sau :
a) NaHSO, + N a O H b) Cu(0H)2 + H C l c) NajHPOa + HCl d) Sn(0H)2 ,r, + H2SO4 c) NajHPOa + HCl d) Sn(0H)2 ,r, + H2SO4
e) MgS04 + NaNO, f) K N O , + NaCl g) S n ( O H) 2+ NaOH h) Cu(N03)2 + H2Ọ g) S n ( O H) 2+ NaOH h) Cu(N03)2 + H2Ọ
Gidi
a) H S O 3 + O H - SỖ + H2O b) Cu( 0 H ) 2 + 2 H ^ - > Cu^* + 2H2O
c) H P O 4 " + 2H* ^ H3PO4 d) Sn(0H)2 + 2 H " -> Sn'^ + 2H2O
e) khong xiiy ra 1) khong X i i y ra
g) Sn(0H)2 + 2 0 H - -> SnÔ" + 2H2O h) Cú* + H.O -> Cu(OH)^ + H ^ Bai 2. V i c t phÚcfng trinh dang phan tur ufng vdi phu'dng trinh ion rut gon sau
a) Câ* + COJ~ > C a C O s i b) Pb^^ + SÔ" > PbSOai
c) S^- + 2 H ^ > H j S t d) H^ + O H " > H2O
c) N H ; + O H " > N H j t + H2O 1) CO2 + 2 0 H - -—> C O ^ + H2Ọ
cm
a) C a C l . + NạCOj > C a C O . i i + 2 N a C l
b) Pb(N0.,)2 + Na2S04 > PbS04i + 2NaN03 c) NạS + 2HC1 > 2 N a C l + H . S t
d) K O H + H C l > K C l + H2O
c) N H 4 C I + NaOH > NaCl + NH3T + H2O 1) C O 2 + 2 K O H v K i C O j + HjỌ 1) C O 2 + 2 K O H v K i C O j + HjỌ
Bai 3.
a) The nao Ih muói trung h6a, muoi axit? Cho vi diị Axit pholphord H3PO3 la axit hai lan axit, vay hdp chat Na2HP03 la muói axit hay muoi trung hoả hai lan axit, vay hdp chat Na2HP03 la muói axit hay muoi trung hoả
b) Vic't phuTdng trlnh ion rut gon cua cac phan iJng thuy phan cac muoi :
NaHCOj, N H 4 C I , H C O O N H 4 , K2SO4. Trong cac phan itng nay núdc dong vai tro axit hay bazd?
Gidi
a)* M u o i trung hoa \h. muói ma anion goc axit khong con hidro c6 kha nang
phan l i ra ion H"^ (hidro co ifnh axit).
V i du : K C l , NajCOj,...
* Muói axit la muói mh anion goc axit con hidro co kha niing phan li ra ion H * .
Vi du : NaHS04, KH2PO4,...
: KHAlgfiVngr
* Na2HP03 la muo'i trung hoạ
b) NaHC03 > Na* + H C O 3 H C O 3 + H2O > H2CO3 + O H " H C O 3 + H2O > H2CO3 + O H " _ H2O dong vai lr5 axit.
N H 4 C 1— > N H ^ + c r
N H ; + H 2 0 > N H 3 + H 3 0 "
_ H2O dong vai tr6 bazd.
H C O O N H 4 > N H : + H C O O " HCOO" + H2O > H C O O H + O H "
N H ; + H2O > NH3 + H3O* _ H2O dong vai tro krSng tinh.
K2SO4 > 2K* + S O ^ -
- NÚdc khong thuy phan nen H2O trung tinh.
Bai 4. Cho bon lo di/ng bon dung djch : HCl, BaCb, K O H , Fe2(S04)3. Nhffng cap dung djch nko c6 the ph5n uTng vdi nhaủ V i saỏ Viét phifdng trinh hoa hoc cua cac phan lirng xay ra du'di dang phan tuf va ion riit gon.
Gidi
* Dung dich H C l phan tfug difdc vdi dung dich K O H HCl + K O H > K C l + H2O
H * + O H - > H2O
* Dung djch BaCb phan uTng diTdc vdi dung dich Fe2(S04)3
3 B a C l 2 + Fe2(S04)3 > 3BaS044 + 2FeCl3 Bâ* + SỖ > BaS044'
* Dung djch K O H phan uTng diTdc vdi dung djch Fe2(S04)3 6 K 0 H + Fe2(S04)3 > 3K2SO4 + 2Fe(OH)3>l'
Fê* + 3 0 H - > Fe(0H)3>l'. Bai 5.
a) Lan liTc^t nhung giay qu>' tim v^o cAc dung djch muoi sau : NH4CI, K N O 3 , Na2S
thl gia'y quy đ co mau gl? Giai thich ng^n gon vil viét phiTdng trinh phAn
tJng minh hoạ
(DH Buu chlnh Vien thon^ TP.HCM) b) Trinh b^y phiTdng phdp h6a hoc nhan bi6't suf c6 m&t cua cac ion trong dung
dich chtfa h5n h(?p ba mu6'i: FeCb, CuCh, AICI3.
(DHAit ninit)
PhSn djng va phuonq phap giai H6a hpc 11 VP cO - D8 Xuan Hung
Gidi
a) Nhung giS'y quy tim v^o Ian liTcft cac muói:
* NH4CI Ihm cho quy tim h6a hong.
Vi dung djch NH4CI c6 moi triTdng axit, pH < 7.
NH4C1 — > NH^ + cr
NH^ + H2O -> NH3 + H3O*
* Dung dich K N O 3: quy tim khong doi maụ
Vi dung dich KNO3 c6 moi triT^ng trung tinh, pH = 7.
KNO3 >K^+ NOJ
Ion K*, NO3 khong c6 kha nang cho vtl nhan proton. * Dung dich Na2S : quy tim hoa xanh. * Dung dich Na2S : quy tim hoa xanh.
Vi dung dich NajS c6 moi triTcfng kiem, pH > 7. NajS > 2Na* + S^" NajS > 2Na* + S^"
S^- + H2O -> HS- + OH" HS" + H2O-> H2S + OH". HS" + H2O-> H2S + OH".
b) Cho dung dich AgN03 v^o hon hcfp gom cac dung dich thay xuát hien ket tua tring AgCl chiJng to c6 ion CI". tring AgCl chiJng to c6 ion CI".
Ag^ + cr > AgCli
* Cho dung dich NH3 diT vao hon hcJp dung dich, ta thay xuat hien dung dieh
mau xanh tham va két tua -> chtfug to c6 ion Cu^""; cho dung dich NaOH du" vao ket tua thu dtfdc thay xuát hien két tua nau do chiJng to c6 ion Fê"", vao ket tua thu dtfdc thay xuát hien két tua nau do chiJng to c6 ion Fê"", sue khi CO2 dir vao dung djch con lai, ta tháy xuát hien két tua keo trfng
A1(0H)3 chu-ng to c6 ion AI^^
FeCb + 3NH3 + 3H2O > Fe(OH)34' + 3NH4CI
(nau do)
AICI3 + 3NH3 + 3H2O > Al(OH)34'+ 3NH4CI
(keo tr^ng)
CUCI2 + 2NH3 + 2H2O > Cu(0H)2>l' + 2NH4CI
Cu(0H)2 + 4NH3 > [Cu(NH3)4](OH)2
(dung dich xanh tham)
A1(0H)3 + NaOH > NaA102 + 2H2O
NaA102 + CO2 + 2H2O > Al(0H)3>t + NaHC03
NaOH + CO2 > NaHC03.
B a i 6.
a) Cho a moi NO2 hap thu hôn toan vao dung dich chiJa a moi NaOH. Dung
dich thu diTdc c6 gii tri pH Idn hdn hay nho hdn 7? Tai saỏ
b) Hoan thanh cac phÚctng trinh sau vh. cho biet chát nao la axit, bazcJ?
C2H5NH2 + H2Q C6H5OH + H2O CH3COO- + H2O CH3O- + H2Ọ
Gidi
a) Phifdngtrinh phan tfng :
2NO2 + 2NaOH > NaNQz + NaNOj + H2O
NaN02 — ^ Na* + NO2 .
NO2 + H2O -> HNO2 + OH"" Do do NO2 la mot bazd p pH > 7.