CHE100
Problem Session #5 - Answers
Instructor: Sherman Henzel
1.
20.0 mol C H x 16 mol CO
2 mol C H = 1.60 x 10 mol CO
818
2
818
2
2
2.
2.500 kg C H x 10 g
kg x 1 mol C H
114.232 g C H x 25 O
2 mol C H x 31.9988 g O
1 mol O = 8754 g O
818
3
818
818
2
818
2
2
2
3.
500.25 g C H x 1 mol C H
114.232 g C H x 18 H O
2 mol C H x 18.015 g H O
1 mol H O = 710.03 g H O
818
818
818
2
818
2
2
2
4.
7.50 x 10 O molecules x 1 mol O
6.02 x 10 O molecules x 16 mol CO
mol O x 44.010 g CO
1 mol CO = 3.51 x 10 g CO
30
2
2
23
2
2
2
2
2
8
2
25
5.
5.00 kg HCl x 1 kmol HCl
36.46 kg HCl x 2 kmol CoCl
6 kmol HCl x 165.292 kg CoCl
1 kmol CoCl = 7.56 kg CoCl
%yield = 5.75 kg
7.56 kg x 100 = 76.1 %
33
3
3
6. gas - widely separated particles; no definite volume, no definite shape; very low density
liquid - particles in contact with one another, but free to within the volume of the liquid;
definite volume; no definite shape; low density
solid - particles are in close contact; definite volume; definite shape; high density
7.
1.25 kg Cu x 10 g
kg x 205 J
g Cu = 2.56 x 10 J
3
5
8.
575.0 g C H x 394 J
g = 2.27 x 10 J
66
5
9.
1.75 x 10 J
25.0 g = 70.0 J
g
3
