Exercise # 2
1. State the mass law(s) demonstrated by the following
experimental results. Show your solutions. Explain in 5 lines
maximum.
Experiment 1:
A student heats 1.00 g of a blue compound and obtains 0.64 g
of a white compound and 0.36 g of a colorless gas.
Experiment 2:
A student heats 3.25 g of the same blue compound and
obtains 2.08 g of a white compound and 1.17 g of a colorless
gas.
2. Show, with calculations, how the following data illustrate the law
of multiple proportions:
Compound 1: 47.5 mass% sulfur; 52.5 mass% chlorine
Compound 2: 31.1 mass% sulfur; 68.9 mass% chlorine
1. Both experiments demonstrate the Law of Conservation of Mass since the
total mass before reaction equals the total mass after reaction. (3 pts)
Experiments 1 and 2 together demonstrate the Law of Definite Composition.
(a) When 3.25 times the amount of blue compound in experiment 1
is used in experiment 2, then 3.25 times the amount of products
were made. OR
(b) The relative amounts of each product are the same in both
experiments. In experiment 1, the ratio of white compound to
colorless gas is 0.64:0.36 or 1.78:1 and in experiment 2, the ratio is
2.08:1.17 or 1.78:1. (4 pts)
2.
47.5 mass % S
Compound 1: 52.5 mass % Cl
= 0.90476 = 0.904
31.1 mass % S
Compound 2:
68.9 mass % Cl
= 0.451379 = 0.451
Ratio:
(3 pts)
0.904
0.451
= 2.0044 = 2.00/1.00