2 9 / O 3 / 2 1
23 1 . Redox Reactions
Reducing and oxidising agents
→
oxidising agent takes e ( gets reduced to oxidise
-
another species )
→
Reducing agent gives e- ( gets oxidised to reduce
another species )
"
Agt oxidising 2
Agt Cag ) t Cu Cs) →
Cee Cag ) + 2 Ages )
agent + I 0 +2 O
Ae
reducing
-
a
n
oxidised
agent
reduced
special species :
→ H in metal hydrides ( H has -
I not + i )
→
Transition Metals
→
O in H 202 (O has -
I not -
2) ( work our charge
→ 0 bonded to F ( e.g Fz O) ( oxidation
.
no . is +2 nor ti ) from home )
NOTE : You rinse the beaker with acid before titrations
2 9 / O 3 I 2 I
23.2 Manganate ( VID redox titrations
procedure : →
note : It is SELF -
INDICATING
I .
Standard Sol .
Of KM nor in burette .
2 . With pipette add a measured nor .
of solution being analysed
to conical flask .
Add excess dit .
Hzsog (to give Ht to reduce
Mn Oa )
-
.
3 .
K Mnoadecolourised ,
end point =
permanent pink colour
( excess Mnoa
-
present ) .
4 Repeat until results are concordant
read from TOP of meniscus
→
readings
"
Mn Og Cag) 8 Ht Cag ) Se →
Mn (ah ) A H2O (c)
-
t t
-
t
BRIGHT PINK ( PURPLE COLOURLESS
, 30 1 04 I 2 I
23.3 Iodine / thiosulfate redox titrations
Titrations
-
1-zlaq )
-
252032
-
involving Izard thiosulfate ( aa )
+ →
54062
-
( as )
determining 21 ( as )
-
the chlorate conc +
-
. in
bleach
Iz (AG )
-
Ze
-
-
LUCID content of Cully compound
+ →
2I (as ) red
deterring 252032 54062 Ze
- -
→
-
Cu content of alloys ox
-
+
-
-
- -
"
2
-
Procedure for analysis of bleach
: 1 ratio → 2 Cu : I
"
52032
-
I .
10.0cm
'
bleach + H2O →
250cm ' v01 flash
1 : I ratio →
2cm :
-
-
2. 25cm ' of Sol into conical flask .
10cm
}
1m01 dn→
- -
KI +
lnordn -3 Ha Cbr Ht )
Analysis of household breach
3 .
Titrate using 0.0s nor dn
-3
Naas 203 1 .
( 10-+21-+211-1 → A
-
+ 12 +
Hzo
( standard 501 ) 252032--1 Iz → ZI 5,062
-
2
-
-
and repeat for concordant results
-
.
+
1m01 CIO 52032
- -
: 1 nor lz : 2 nor
- -
-
-
( alloy + HNO } , neutralization )
Analysis of Cu Cu (s ) → Cutlass
-
( )
cured # → +1
1. ZCU
"
4I 2. Guy Iz Thiosulfate in burette
-
+
-
+ → I ox -
no
-
-
2.
252032
-
+
Iz → 21-+54062
-
( cut Koi -
) -
→
-
Oxidising Agent in conical flask
-
Analysis of oxidising agents
prepare Sol . of Oxidising agent reacts w/
standard son ol .
> ☐ ✗ idisin-9 agent - I
-
to produce Iz ( turns
,
Nazszoz to burette use pipette add yellow -
brown )
to 501 in conical
t
.
flask
Starch indicator -
Iz reduced back to I
-
used to determine and brown colour fades <
Titrate for with Nazszoz
end point ( quite gradually (
.
makes it straw
pale
colour)
blue -
black )
as Iz appears )÷( →
)÷( →
)÷( yellow -
brown
/ ¥1 I :-| / \
yeuow
-
mom ÷ colour fades
mama coma #
starch makes
Iz turn
)÷( )÷( →
)÷/ At endpoint -
bluey
sa →
;± y I :-| #-) III.
-
black disappears can
* smokiest
-
±
blue -
black fades
near end point
23 1 . Redox Reactions
Reducing and oxidising agents
→
oxidising agent takes e ( gets reduced to oxidise
-
another species )
→
Reducing agent gives e- ( gets oxidised to reduce
another species )
"
Agt oxidising 2
Agt Cag ) t Cu Cs) →
Cee Cag ) + 2 Ages )
agent + I 0 +2 O
Ae
reducing
-
a
n
oxidised
agent
reduced
special species :
→ H in metal hydrides ( H has -
I not + i )
→
Transition Metals
→
O in H 202 (O has -
I not -
2) ( work our charge
→ 0 bonded to F ( e.g Fz O) ( oxidation
.
no . is +2 nor ti ) from home )
NOTE : You rinse the beaker with acid before titrations
2 9 / O 3 I 2 I
23.2 Manganate ( VID redox titrations
procedure : →
note : It is SELF -
INDICATING
I .
Standard Sol .
Of KM nor in burette .
2 . With pipette add a measured nor .
of solution being analysed
to conical flask .
Add excess dit .
Hzsog (to give Ht to reduce
Mn Oa )
-
.
3 .
K Mnoadecolourised ,
end point =
permanent pink colour
( excess Mnoa
-
present ) .
4 Repeat until results are concordant
read from TOP of meniscus
→
readings
"
Mn Og Cag) 8 Ht Cag ) Se →
Mn (ah ) A H2O (c)
-
t t
-
t
BRIGHT PINK ( PURPLE COLOURLESS
, 30 1 04 I 2 I
23.3 Iodine / thiosulfate redox titrations
Titrations
-
1-zlaq )
-
252032
-
involving Izard thiosulfate ( aa )
+ →
54062
-
( as )
determining 21 ( as )
-
the chlorate conc +
-
. in
bleach
Iz (AG )
-
Ze
-
-
LUCID content of Cully compound
+ →
2I (as ) red
deterring 252032 54062 Ze
- -
→
-
Cu content of alloys ox
-
+
-
-
- -
"
2
-
Procedure for analysis of bleach
: 1 ratio → 2 Cu : I
"
52032
-
I .
10.0cm
'
bleach + H2O →
250cm ' v01 flash
1 : I ratio →
2cm :
-
-
2. 25cm ' of Sol into conical flask .
10cm
}
1m01 dn→
- -
KI +
lnordn -3 Ha Cbr Ht )
Analysis of household breach
3 .
Titrate using 0.0s nor dn
-3
Naas 203 1 .
( 10-+21-+211-1 → A
-
+ 12 +
Hzo
( standard 501 ) 252032--1 Iz → ZI 5,062
-
2
-
-
and repeat for concordant results
-
.
+
1m01 CIO 52032
- -
: 1 nor lz : 2 nor
- -
-
-
( alloy + HNO } , neutralization )
Analysis of Cu Cu (s ) → Cutlass
-
( )
cured # → +1
1. ZCU
"
4I 2. Guy Iz Thiosulfate in burette
-
+
-
+ → I ox -
no
-
-
2.
252032
-
+
Iz → 21-+54062
-
( cut Koi -
) -
→
-
Oxidising Agent in conical flask
-
Analysis of oxidising agents
prepare Sol . of Oxidising agent reacts w/
standard son ol .
> ☐ ✗ idisin-9 agent - I
-
to produce Iz ( turns
,
Nazszoz to burette use pipette add yellow -
brown )
to 501 in conical
t
.
flask
Starch indicator -
Iz reduced back to I
-
used to determine and brown colour fades <
Titrate for with Nazszoz
end point ( quite gradually (
.
makes it straw
pale
colour)
blue -
black )
as Iz appears )÷( →
)÷( →
)÷( yellow -
brown
/ ¥1 I :-| / \
yeuow
-
mom ÷ colour fades
mama coma #
starch makes
Iz turn
)÷( )÷( →
)÷/ At endpoint -
bluey
sa →
;± y I :-| #-) III.
-
black disappears can
* smokiest
-
±
blue -
black fades
near end point
