Front matter

Dissertation

presented for the degree of Doctor of Philosophy to the Board of University Studies of the Johns Hopkins University

by Arthur John Hopkins. 1893.

Acknowledgment——

The work recorded in this paper is the result of a suggestion given by Professor H. N. Morse. It has received his careful attention throughout its course. For his instruction and exact criticism, I wish to offer my acknowledgment and thanks. I wish also to express to Professor Ira Remson my appreciation of his interest and instruction and to offer to Dr. J. S. Ames my thanks for his instruction in Physics——

Table of Contents.

Page.

I Introduction 1

II Description of Apparatus 3

III Action of Manganese Dioxide on

Potassium Permanganate in acid solution 9

IV Action of a Black Oxide of Manganese on

Potassium Permanganate 24

V The Amount of Nitric Acid Neutralized 31

VI The Stability of Manganese Dioxide 34

VII The Effect of Varying Quantities of

Manganese Oxide and Potassium Permanganate 39

VIII The Reduction of Neutral Potassium Permanganate

by Manganese Oxide at Ordinary Temperature 45

IX Action of Potassium Permanganate upon a

Manganese Oxide Obtained from Manganese

Dioxide by Spontaneous Decomposition 50

Conclusion