186
Stoichiometry II. Calculations Based on Chemical Equations
(b) How many moles of H 2 SO 4 are needed
1 (The reaction is given in Problem
24)
33 What volume of O 2 , collected over water at 735 torr and 20°C, can be produced from 4 00 Ib of sodium peroxide, Na 2 O 2 , according to the reaction
2Na,0 2 + 2H 2 O -^ 4NaOH + O 2
34 (a) What weight of NaNO 3 is needed to produce 5 00 liters of N 2 O collected
over water at 737 torr and 27°C
J The reaction is
NH 4 C1 + NaNO 3 4- NaCl + N 2 O + 2H 2 O
(b) How many moles of NH 4 C1 are needed"
7
35 (a) What volume of NH 3 at 700 torr and 50°C is needed to make 5 00 Ib of
CV The reaction is
3NH 3 + H 3 PO 4 -
(b) What volume of H 3 PO 4 (density = 1 69 g/ml, 85% H 5 PO 4 by weight) is
needed for this preparation
9
36 (a) What volume of H 2 SO 4 (density = 1 84 g/ml, 9<>% H 2 SO 4 by weight) is
needed to produce 8 30 liters of H 2 collected over water at 740 torr and
18°C
7 The reaction is
Mg + H 2 SO 4 -^ MgSO 4 + H 2
(b) How many moles of Mg are used
1
37 What volume of air (2 1 % O 2 by volume) at 720 torr and 68°F is needed to burn
1 00 Ib of butane gas, C 4 H 10 > Balance the equation before solving the problem
C 4 H 10 + O 2 ^ CO 2 + H 2 O
38 In the process of photosynthesis, plants use CO 2 and water to produce sugars
according to the overall reaction
11H 2 O+ 12CO 2 ^ C 12 H 22 O U + 12O 2
(a) What volume of CO 2 at 30°C and 730 torr is used by a plant in making 1 00
Ib of sucrose, C 12 H 22 O n '
(b) What volume of air is deprived of its normal amount of CO 2 in this process
9 (Air contains 0 035% CO 2 by volume Assume a barometric pressure
of 750 torr and a temperature of 70°F)
39 A big national industry produces ethyl alcohol, C 2 H 5 OH, by the enzymatic
action of yeast on sugar, by the reaction
C 6 H 12 0 6 -^^ 2C 2 H 5 OH + 2C0 2
What volume of CO 2 at 720 torr and 30°C is formed during the production of
100 gal of alcohol that is 95% C 2 H 5 OH by weight
7 (The density of 95%
C 2 H 5 OH is 0 800 g/ml )
Stoichiometry II. Calculations Based on Chemical Equations
(b) How many moles of H 2 SO 4 are needed
1 (The reaction is given in Problem
24)
33 What volume of O 2 , collected over water at 735 torr and 20°C, can be produced from 4 00 Ib of sodium peroxide, Na 2 O 2 , according to the reaction
2Na,0 2 + 2H 2 O -^ 4NaOH + O 2
34 (a) What weight of NaNO 3 is needed to produce 5 00 liters of N 2 O collected
over water at 737 torr and 27°C
J The reaction is
NH 4 C1 + NaNO 3 4- NaCl + N 2 O + 2H 2 O
(b) How many moles of NH 4 C1 are needed"
7
35 (a) What volume of NH 3 at 700 torr and 50°C is needed to make 5 00 Ib of
CV The reaction is
3NH 3 + H 3 PO 4 -
(b) What volume of H 3 PO 4 (density = 1 69 g/ml, 85% H 5 PO 4 by weight) is
needed for this preparation
9
36 (a) What volume of H 2 SO 4 (density = 1 84 g/ml, 9<>% H 2 SO 4 by weight) is
needed to produce 8 30 liters of H 2 collected over water at 740 torr and
18°C
7 The reaction is
Mg + H 2 SO 4 -^ MgSO 4 + H 2
(b) How many moles of Mg are used
1
37 What volume of air (2 1 % O 2 by volume) at 720 torr and 68°F is needed to burn
1 00 Ib of butane gas, C 4 H 10 > Balance the equation before solving the problem
C 4 H 10 + O 2 ^ CO 2 + H 2 O
38 In the process of photosynthesis, plants use CO 2 and water to produce sugars
according to the overall reaction
11H 2 O+ 12CO 2 ^ C 12 H 22 O U + 12O 2
(a) What volume of CO 2 at 30°C and 730 torr is used by a plant in making 1 00
Ib of sucrose, C 12 H 22 O n '
(b) What volume of air is deprived of its normal amount of CO 2 in this process
9 (Air contains 0 035% CO 2 by volume Assume a barometric pressure
of 750 torr and a temperature of 70°F)
39 A big national industry produces ethyl alcohol, C 2 H 5 OH, by the enzymatic
action of yeast on sugar, by the reaction
C 6 H 12 0 6 -^^ 2C 2 H 5 OH + 2C0 2
What volume of CO 2 at 720 torr and 30°C is formed during the production of
100 gal of alcohol that is 95% C 2 H 5 OH by weight
7 (The density of 95%
C 2 H 5 OH is 0 800 g/ml )