Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1  2
Author: Subject: I made some nitric acid
DerAlte
National Hazard
****




Posts: 779
Registered: 14-5-2007
Location: Erehwon
Member Is Offline

Mood: Disgusted

[*] posted on 18-10-2012 at 21:32


The Birkeland-Eyde is incredibly inefficient due to the endothermic nature of the reaction. It has been obsolete for nearly a century. Henry Cavendish first demonstated the process in 1784 (Wiki). The equilibrium of the reaction N2 + O2 -- > 2NO lies slightly to the right at 1500C (0.4%) and being endothermic, by Le Chatelier’s principle,increases to ~5% at 3000C. The reaction has to be initiated by the dissociation N2 -- > 2N which requires 945 kjoules. The amount of oxygen in a 2L flask is 2/22.4*28.8 *0.21 = 0.5 g. So, if you can arc at 3000C, from the overall reaction N2 +2 O2 -- > 2NO2 you’ll get at max. 0.05* 0.5*48 N/92 g = 14 mg NO2 – enough to color the gas in the flask. And produce a tiny drip of acid… Hardly a "shitload"!

Good experiment demonstrating principle, no use for any useful product.

The reason your FBT blew up is that normally it produces a milliamp or so needed for the 25 - 40 kv acceleration of the electron beam to the phosphor screen. You shorted it with your arc. Very unkind!

As for using Microwave oven transformers, be aware that these SOBs are LETHAL with their 1.5 KVA at c. 1KV. Modern ones use switched power supplies at >>50Hz for weight reduction; don't mess with either type.
View user's profile View All Posts By User
 Pages:  1  2

  Go To Top