Download Problem Set 13

CHEM 109
Introduction to Chemistry
Fall 2016
Problem Set 13
Reading for Today
Fundamental Laws Handout
Reading for Next Tuesday
Selection from The Development of Modern Chemistry by Aason J. Ihde
Additional Problems
1.
Mercury forms two different Oxides; Mercurous Oxide and Mercuric Oxide. The relative
amounts of mercury and oxygen in these compounds are:
Mercurous Oxide
Mercuric Oxide
mass Mercury 1.00g
1.00g
mass Oxygen 0.0395g
0.0799g
Form the following ratio:
(mass O in Mercuric Ox. / mass Hg) / (mass O in Mercurous Ox. / mass Hg)
Is the result consistent with the Law of Multiple Proportions?
2.
Use the data of Problem 9 of Problem Set 12 to form the following ratio:
(mass Se in Cmpd. #2 / mass P) / (mass Se in Cmpd. #1 / mass P)
Is the result consistent with the Law of Multiple Proportions?
3.
Oxygen reacts readily with Sodium to form two different compounds; Sodium Oxide
(0.348g O per gram Na) and Sodium Peroxide (0.696g O per gram Na). Form the
following ratio:
Is the result consistent with the Law of Multiple Proportions?
4.
Iodine reacts with Fluorine to form a number of compounds. The mass of Fluorine
required to react with 1.00g of Iodine to form three of these compounds is:
Compound
1
2
3
Mass Fluorine/1.00g Iodine
0.4490
0.7495
1.0478
Form the following ratios.
For each case, show these ratios can be written as a ratio of small whole numbers;
consistent with the Law of Multiple Proportions. Think in terms of fractions:
1/4 = 0.25, 1/2 = 0.5, 3/4 = 0.75, 1/3 = 0.333, 2/3 = 0.667
5.
Nitrogen forms many different Oxides, two of which are Nitrous Oxide (1.747g N per gram
Oxygen) and Nitric Oxide (0.876g N per gram Oxygen). Form the following ratio:
Propose chemical formulas for each of these compounds that are consistent with this
Multiple Proportions result. Look-up the formulas for each compound. Are they the same?
Comment.
6.
Gold forms two different compounds with chlorine:
Aurous chloride
84.76%
Au
15.24%
Cl
Auric chloride
64.94%
Au
35.06%
Cl
a) Calculate the mass of Chlorine required to react with 1.00g of Gold to form each of
these compounds.
b) Form the following ratio:
(mass Cl in Auric Chl. / mass Au) / (mass Cl in Aurous Chl. / mass Au)
Is the result consistent with the Law of Multiple Proportions?
c) Suggest reasonable chemical formulas for Aurous Chloride and Auric Chloride.