Problems B
201
17 A 0 500 g sample of impure CaCO 3 is dissolved in 50 0 ml of 0 100 M HC1 and
the residual acid titrated by 5 00 ml of 0 120 M NaOH Find the percentage of
CaCO 3 in the sample The reaction is
CaC0 3 + 2HC1 -^ CaCl 2 + H 2 O + CO 2
18 It takes 45 00 ml of a given HC1 solution to react with 0 2435 g calcite CaCO 3
This acid is used to determine the percent purity of a Ba(OH) 2 sample as
follows
Wt of impure Ba(OH) 2 sample = 0 4367 g
Vol of HC1 used - 35 27 ml
Vol of NaOH used for back-titration = 1 78 ml
1 200 ml of HC1 titrates 1 312 ml of NaOH
What is the percentage of Ba(OH) 2 in the sample'
19 (a) What weight of AgCl can be obtained by precipitating all the Ag
+ from 50
ml of 0 12 M AgNO 3 '
(b) What weight of NaCl is required to precipitate the AgCl'
(c) What volume of 0 24 M HC1 would be needed to precipitate the AgCl
9
20 What volume of 10 0 M HC1 is needed to prepare 6 40 liters H 2 S at 750 torr and
27°C
9 The reaction is
FeS + 2HC1 -> FeCl 2 + H 2 S
21 What volume of 12 5 M NaOH is needed to prepare 25 0 liters of H 2 at 735 torr
and 18°C by the reaction
2A1 + 2NaOH + 2H 2 O -> 2NaAlO 2 + 3H 2
22 (a) What weight of silver and what volume of 6 00 M HNO 3 are needed for the
preparation of 500 ml of 3 00 M AgNO 3 '
(b) What volume of NO, collected over water at 725 torr and 27°C, will be
formed"
7 The reaction is
3Ag + 4HNO 3 -^ 3AgNO, + NO + 2H 2 O
23 Fuming sulfunc acid is a mixture of H 2 SO 4 and SO 3 A 2 500 g sample of
fuming sulfunc acid requires 47 53 ml of 1 1513 M NaOH for titration What is
the percentage of SO 3 in the sample
9
PROBLEMS B
24 Tell how you would prepare each of the following solutions
(a) 125 ml of 0 62 M NH 4 C1 from solid NH 4 C1
(b) 2 75 liters of 1 72 M Ni(NO 3 ) 2 from solid Ni(NO,)2 6H 2 O
(c) 65 0 ml of 0 25 M Al(NOi) 3 from solid Al(NO 3 )j 9H 2 O
201
17 A 0 500 g sample of impure CaCO 3 is dissolved in 50 0 ml of 0 100 M HC1 and
the residual acid titrated by 5 00 ml of 0 120 M NaOH Find the percentage of
CaCO 3 in the sample The reaction is
CaC0 3 + 2HC1 -^ CaCl 2 + H 2 O + CO 2
18 It takes 45 00 ml of a given HC1 solution to react with 0 2435 g calcite CaCO 3
This acid is used to determine the percent purity of a Ba(OH) 2 sample as
follows
Wt of impure Ba(OH) 2 sample = 0 4367 g
Vol of HC1 used - 35 27 ml
Vol of NaOH used for back-titration = 1 78 ml
1 200 ml of HC1 titrates 1 312 ml of NaOH
What is the percentage of Ba(OH) 2 in the sample'
19 (a) What weight of AgCl can be obtained by precipitating all the Ag
+ from 50
ml of 0 12 M AgNO 3 '
(b) What weight of NaCl is required to precipitate the AgCl'
(c) What volume of 0 24 M HC1 would be needed to precipitate the AgCl
9
20 What volume of 10 0 M HC1 is needed to prepare 6 40 liters H 2 S at 750 torr and
27°C
9 The reaction is
FeS + 2HC1 -> FeCl 2 + H 2 S
21 What volume of 12 5 M NaOH is needed to prepare 25 0 liters of H 2 at 735 torr
and 18°C by the reaction
2A1 + 2NaOH + 2H 2 O -> 2NaAlO 2 + 3H 2
22 (a) What weight of silver and what volume of 6 00 M HNO 3 are needed for the
preparation of 500 ml of 3 00 M AgNO 3 '
(b) What volume of NO, collected over water at 725 torr and 27°C, will be
formed"
7 The reaction is
3Ag + 4HNO 3 -^ 3AgNO, + NO + 2H 2 O
23 Fuming sulfunc acid is a mixture of H 2 SO 4 and SO 3 A 2 500 g sample of
fuming sulfunc acid requires 47 53 ml of 1 1513 M NaOH for titration What is
the percentage of SO 3 in the sample
9
PROBLEMS B
24 Tell how you would prepare each of the following solutions
(a) 125 ml of 0 62 M NH 4 C1 from solid NH 4 C1
(b) 2 75 liters of 1 72 M Ni(NO 3 ) 2 from solid Ni(NO,)2 6H 2 O
(c) 65 0 ml of 0 25 M Al(NOi) 3 from solid Al(NO 3 )j 9H 2 O