examens-nationaux-2bac-pc-2018-r

6 1
P a g e
6
2018
-  -
RS 27
o  3
o 2 5
o 3

6 2
6
 2018
–
RS 
0,5 0,5 1 0,5
0,5 0,75 0,75
0,75 0,25
3
CH COOH
(°)
()g
100 mL
25 C
33
( ( )/ ( )) 4,8
A
pK CH COOH aq CH COO aq
1
3
( ) 60 .M CH COOH g mol
pH
25 C
3,0pH 
33
( )/ ( )CH COOH aq CH COO aq
,r éq
Q
,r éq
Q
6
0
C
pH
1
()S
25
A
V mL
1
()S
A
C
0
()
10
AC
C
2
()S
( ) ( )aq aq
Na HO
11
2,5.10 .
B
C mol L
2
()S
,E 10 B
V mL
A
C
0
C
10,3 n mol
20,3 n mol
( ) 0,2
f
n ester mol
3 ( ) 2 5 ( ) 3 2 5( ) 2 ( )
CH COOH C H OH CH COOC H H O

6 3
6
 2018
–
RS 
0,5 0,5 0,5
0,5 0,75 0,75
0,5 
0,5
K
230
90Th
234
92U
230
90Th
234
92U
234
92U
234
92U
234
92U
MeV
86321,9
133418,5
218009,1
230
90Th
234
92U
234
92U
3
1,65.10 MeV
3
1,73.10 MeV
3
1,85.10 MeV
3
1,98.10 MeV
00t
0
N
0
a
00t
a
t
0
a
ln a
1
()an
1
t
02
a
a
1
t
()an

6 4
6
 2018
–
RS 
0,75
0,75 0,25
0,5 
0,5 0,25
RC
RLC
E
C
( ; 0)Lr
16 Rk
2
R
K
RC
00t
()
C
ut
C
u
1.
CC
du E
u
dt
E
6,3 CF
K
00t
()
C
ut
0
Q
00t
T

6 5
6
 2018
–
RS 
0,5
0,5 1
T
()LC
L
210
Ee
Em
E
E E E
em
Em
E
00t
13 t ms
5
AB
BCLDE