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Stoichlometry IV: Equivalent Weight and Normality
12. A soda-lime sample is 85.0% NaOH and 15.0% CaO.
(a) If 3.50 g are dissolved in a volume of 300 ml, what is the normality of this
solution?
(b) How many ml of 0.5000 N H 2 SO 4 would be required to titrate 1.000 ml of
the solution?
13. What is the normality of a mixture of H 2 SO 4 and HNO 3 if 28.76 ml are required to titrate a 0.4517 g sample of pure Na 2 CO 3 ?
14. What volume of 5.00 N HC1 is needed to prepare 12.7 liters of CO 2 at 735 torr
and 35.0°C? (CaCO 3 is used as the source of CO 2 .)
15. (a) What weight of MnO 2 and (b) what volume of 12.0 N HC1 are needed for
the preparation of 750 ml of 2.00 M MnCl 2 ? (c) What volume of C1 2 at 745
torr and 23.0°C will also be formed?
16. The amount of CaCO 3 in a sample may be determined by dissolving the
sample and precipitating the Ca as CaC 2 O 4 . This precipitate may be washed
and dissolved in H 2 SO 4 , and the C 2 O 4 ~ titrated with standard KMnO 4 solution.
Following this procedure, the CaC 2 O 4 from a 0.4526 g sample of limestone is
dissolved in H 2 SO 4 . The resulting solution requires 41.60 ml of 0.1000 N
KMnO 4 for titration. What is the percentage of CaCO 3 in the original sample?
17. Any of Problems 12 through 23 in Chapter 13 would be suitable for solution by
the principles involving equivalents.
PROBLEMS B
18. Tell how you would prepare each of the following solutions.
(a) 5.50 liters of 0.600 N LiOH from solid LiOH
(b) 2.80 liters of 0.0100 N Sr(OH) 2 from solid Sr(OH) 2
(c) 350 ml of 3.50 N FeCl 3 from solid FeCl 3 • 6H 2 O
19. Tell how you would prepare each of the following solutions.
(a) 5.32 liters of 1.20 M CdCl 2 from 6.85 N CdCl 2
(b) 600 ml of 2.50 N H 3 PO 4 from 12.0 M H 3 PO 4
(c) 6.30 liters of 0.00300 M Ba(OH) 2 from 0.100 N Ba(OH) 2
(d) 15.8 liters of 0.320 N NH 3 from 8.00 M NH 3
20. Tell how you would prepare each of the following solutions (weight percentage given).
(a) 500 ml of 0.200 N HC1O 4 from a 50.0% solution whose density is 1.410
g/ml
(b) 2.50 liters of 1.50 N H 3 PO 4 from an 85.0% solution whose density is 1.689
g/ml
(c) 750 ml of 0.250 N Cr 2 (SO 4 ) 3 from a 35.0% solution whose density is 1.412
g/ml.
21. What volume of 0.0800 M NaOH is needed for the titration of 30.00 ml of
0.1100 M H 2 SO 4 ?
Stoichlometry IV: Equivalent Weight and Normality
12. A soda-lime sample is 85.0% NaOH and 15.0% CaO.
(a) If 3.50 g are dissolved in a volume of 300 ml, what is the normality of this
solution?
(b) How many ml of 0.5000 N H 2 SO 4 would be required to titrate 1.000 ml of
the solution?
13. What is the normality of a mixture of H 2 SO 4 and HNO 3 if 28.76 ml are required to titrate a 0.4517 g sample of pure Na 2 CO 3 ?
14. What volume of 5.00 N HC1 is needed to prepare 12.7 liters of CO 2 at 735 torr
and 35.0°C? (CaCO 3 is used as the source of CO 2 .)
15. (a) What weight of MnO 2 and (b) what volume of 12.0 N HC1 are needed for
the preparation of 750 ml of 2.00 M MnCl 2 ? (c) What volume of C1 2 at 745
torr and 23.0°C will also be formed?
16. The amount of CaCO 3 in a sample may be determined by dissolving the
sample and precipitating the Ca as CaC 2 O 4 . This precipitate may be washed
and dissolved in H 2 SO 4 , and the C 2 O 4 ~ titrated with standard KMnO 4 solution.
Following this procedure, the CaC 2 O 4 from a 0.4526 g sample of limestone is
dissolved in H 2 SO 4 . The resulting solution requires 41.60 ml of 0.1000 N
KMnO 4 for titration. What is the percentage of CaCO 3 in the original sample?
17. Any of Problems 12 through 23 in Chapter 13 would be suitable for solution by
the principles involving equivalents.
PROBLEMS B
18. Tell how you would prepare each of the following solutions.
(a) 5.50 liters of 0.600 N LiOH from solid LiOH
(b) 2.80 liters of 0.0100 N Sr(OH) 2 from solid Sr(OH) 2
(c) 350 ml of 3.50 N FeCl 3 from solid FeCl 3 • 6H 2 O
19. Tell how you would prepare each of the following solutions.
(a) 5.32 liters of 1.20 M CdCl 2 from 6.85 N CdCl 2
(b) 600 ml of 2.50 N H 3 PO 4 from 12.0 M H 3 PO 4
(c) 6.30 liters of 0.00300 M Ba(OH) 2 from 0.100 N Ba(OH) 2
(d) 15.8 liters of 0.320 N NH 3 from 8.00 M NH 3
20. Tell how you would prepare each of the following solutions (weight percentage given).
(a) 500 ml of 0.200 N HC1O 4 from a 50.0% solution whose density is 1.410
g/ml
(b) 2.50 liters of 1.50 N H 3 PO 4 from an 85.0% solution whose density is 1.689
g/ml
(c) 750 ml of 0.250 N Cr 2 (SO 4 ) 3 from a 35.0% solution whose density is 1.412
g/ml.
21. What volume of 0.0800 M NaOH is needed for the titration of 30.00 ml of
0.1100 M H 2 SO 4 ?