Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Perrhenic acid
open-in-new
<p>Perrhenic acid is the <a href="/facts/Chemical_compound/37FXqqtv">chemical compound</a> with the formula Re2O7(H2O)2. It is obtained by evaporating aqueous solutions of Re2O7. Conventionally, perrhenic acid is considered to have the formula HReO4, and a species of this formula forms when rhenium(VII) oxide sublimes in the presence of water or steam. When a solution of Re2O7 is kept for a period of months, it breaks down and crystals of HReO4·H2O are formed, which contain tetrahedral ReO−4. For most purposes, perrhenic acid and <a href="/facts/Rhenium(VII)_oxide/QBUcnAeD">rhenium(VII) oxide</a> are used interchangeably. <a href="/facts/Rhenium/TzyqJYEn">Rhenium</a> can be dissolved in <a href="/facts/Nitric_acid/UDbwGp6s">nitric</a> or concentrated <a href="/facts/Sulfuric_acid/Wom6fymJ">sulfuric acid</a> to produce perrhenic acid. </p>