User contributions for Woelen

24 October 2021

• 21:1521:15, 24 October 2021 diff hist −7 m Sodium sulfite Sodium sulfite is purely white, not pale yellow.

16 October 2021

• 17:2117:21, 16 October 2021 diff hist +107 m Chlorosulfuric acid Added remark on appearance in samples, occuring in practice.

23 August 2021

• 08:4708:47, 23 August 2021 diff hist −11 m Sodium dithionite The material is stable in dry air, does not require absence of air.
• 08:4508:45, 23 August 2021 diff hist −4 m Sodium dithionite Minor change, removed link to stable (for horses, cows and so on).

26 April 2021

• 09:5509:55, 26 April 2021 diff hist −6 m Tert-Butyl hypochlorite Not colorless, but yellow.

14 March 2020

• 21:1321:13, 14 March 2020 diff hist 0 Rhenium fixed typo
• 21:1221:12, 14 March 2020 diff hist 0 m Rhenium fixed typo
• 21:1221:12, 14 March 2020 diff hist +4 m Rhenium Corrected color of Re2O7 and mention of red color of ReO3.

4 August 2019

• 17:5317:53, 4 August 2019 diff hist +1 m Magnesium chromate The color of this solid is yellow, not white or brown.

28 May 2019

• 21:1721:17, 28 May 2019 diff hist +152 m Boron tribromide Added picture of the pure compound.
• 21:0621:06, 28 May 2019 diff hist +71 m Phosphorus triiodide Added picture of the pure compound.

12 April 2018

• 08:2708:27, 12 April 2018 diff hist +44 m Potassium persulfate No edit summary

27 March 2018

• 11:0611:06, 27 March 2018 diff hist −37 m Ammonium azide Removed remark about low solubility in water. It is quite soluble, according to my own experience.

22 March 2018

• 11:5911:59, 22 March 2018 diff hist −40 m Copper(II) azide →The reaction equation, written here is nonsense, from concentrated HNO3 you don't get hydroxides.

19 February 2018

• 15:2315:23, 19 February 2018 diff hist −5 m Phosphorus pentoxide The solid is odorless, however, if the dust is inhaled, this leads to strong irritation.

12 February 2018

• 16:1916:19, 12 February 2018 diff hist +53 m Sodium chlorite Reorganized a sentence and rephrased somewhat.

24 January 2018

• 14:1814:18, 24 January 2018 diff hist +8 m Chlorine azide The gas is colorless. A solution of this compound in water is yellow. Never saw the pure liquid.

7 August 2017

• 09:2209:22, 7 August 2017 diff hist −5 m Trifluoronitrosomethane Edited some safety info, based on MSDS of actual supplier: http://www.synquestlabs.com/msds/4145-2-01.pdf

14 February 2017

• 12:5912:59, 14 February 2017 diff hist +1 m Sodium periodate No edit summary

22 November 2016

• 16:1516:15, 22 November 2016 diff hist +3 m Interhalogen Minor edit, fixed small error

9 October 2016

• 19:4419:44, 9 October 2016 diff hist +2 m Bromine monochloride Very minor changes, described gas as 'reactive' instead of the very general 'unstable'. The gas is quite stable if kept in a glass container, separate from other chemicals and can be stored indefinitely.

6 October 2016

• 11:2611:26, 6 October 2016 diff hist +20 Chromium(VI) oxide peroxide No edit summary

1 October 2015

• 14:4814:48, 1 October 2015 diff hist 0 m Arsenic trichloride Changed some numbers in the NFPA diamond

11 September 2015

• 19:4919:49, 11 September 2015 diff hist +11 m Vanadium(IV) oxide No edit summary

8 September 2015

• 14:0414:04, 8 September 2015 diff hist +1 m Color of chemicals →Metals
• 14:0314:03, 8 September 2015 diff hist +104 Color of chemicals →Gases
• 13:5713:57, 8 September 2015 diff hist 0 Color of chemicals →Ions in aqueous solution
• 13:5613:56, 8 September 2015 diff hist +321 m Color of chemicals Fixed some colors and names of complexes (not ammonium complexes, but ammine complexes)

18 August 2015

• 10:5110:51, 18 August 2015 diff hist 0 m Copper(II) azide Edited NFPA-rating for flammability. The material is not highly volatile and flammable. On heating it explodes.

2 April 2015

• 09:2509:25, 2 April 2015 diff hist −3 m Chromyl chloride →Preparation

13 June 2014

• 19:3919:39, 13 June 2014 diff hist 0 m Arsenic pentoxide This is an extremely toxic compound. and needs class 4 for toxicity.

31 May 2014

• 19:0319:03, 31 May 2014 diff hist −2 m Uranyl nitrate fixed typo
• 19:0219:02, 31 May 2014 diff hist +2 m Uranyl nitrate The displayed material is crystalline, not a powder

5 May 2013

• 19:4719:47, 5 May 2013 diff hist +14 Potassium metabisulfite At 190 C there is no decomposition to K2O, decomposition does not go further than K2SO3 at this low temperature.

31 March 2013

• 12:5612:56, 31 March 2013 diff hist +13 m Thallium(III) oxide Color of the oxide is not colorless, but nearly black.

24 February 2013

• 21:0821:08, 24 February 2013 diff hist −1 m Nitric acid The yellow acid is fuming acid, at least 90% HNO3
• 20:5920:59, 24 February 2013 diff hist +27 Caesium perchlorate From experience I can say that CsClO4 is not hygroscopic at all.

14 November 2011

• 16:4316:43, 14 November 2011 diff hist +96 Phosphorus tribromide Added picture of almost 20 ml of PBr3, which is slightly yellow, due to remains of Br2 or PBr5.
• 16:4116:41, 14 November 2011 diff hist +51 Phosphoryl chloride Added picture of 100 ml of POCl3 in a glass bottle.

3 July 2011

• 20:0920:09, 3 July 2011 diff hist +23 Cerium oxalate Added picture of cerium(III) oxalate. Alse changed description of color. Cerium(III) compounds are white, while cerium(IV) compounds can be yellow. This compound is NOT hygroscopic at all (personal experience).
• 18:5718:57, 3 July 2011 diff hist +106 Butanone Added picture of 45 ml of MEK
• 18:5118:51, 3 July 2011 diff hist +77 Acetic acid Added picture of bottle of reagent grade acetic acid. (Why doesn't it go below the ImageFileL2 and ImageFileR2???)
• 14:0114:01, 3 July 2011 diff hist +271 Ethylenediamine Added pictures of this compound, a bottle with colorless liquid and the same bottle opened, such that it fumes in humid air.

20 June 2011

• 20:0320:03, 20 June 2011 diff hist +1 Osmium tetroxide Image position
• 19:4919:49, 20 June 2011 diff hist +255 Perchloric acid HClO4 is a strong oxidizer, but only above 70%. Even boiling 70% HClO4 is not capable of oxidizing a facile reductor like Na2SO3 or KI at an appreciable rate (I know this from experience).
• 19:4319:43, 20 June 2011 diff hist +80 Perchloric acid Added picture of 60 percent perchloric acid.
• 19:2119:21, 20 June 2011 diff hist +1 Phenol Replaced text 'blue green crystalline solid' by 'transparent crystalline solid'
• 19:1919:19, 20 June 2011 diff hist +59 Phenol Added picture of appr. 2 grams of phenol. It is a transparent glassy appearing solid.
• 18:5818:58, 20 June 2011 diff hist +62 Sodium borohydride Added picture of 25 grams of sodium borohydride.
• 18:4118:41, 20 June 2011 diff hist +69 Nitric acid Added picture of 70% acid, showing typical slight yellow coloration.