Tuesday, April 8, 2014

My Question: Hi, we have for the last time in chemistry, the acid hydrolysis of sucrose to the Fehl


New issue
Answers Forum overview -> Organic Chemistry Author Message Bubu Joined: 22/01/2012 Beitrge: itis 13 Posted: 01 May 2012 11:57 Title: sucrose
My Question: Hi, we have for the last time in chemistry, the acid hydrolysis of sucrose to the Fehling's test, the glucose oxidase test and the Seliwanow sample tested. All samples were positive and I now have the question of how it can be that the Fehling's test, and at the same time the Seliwanow-sample is positive? My ideas: If the Fehling's test is positive, this indicates but to an aldehyde group out, but when the Seliwanow sample is positive, the majority do not because that no aldehyde group is present? magician4 Moderator Joined: 05/10/2009 Beitrge: 8281 Location: Hamburg itis Posted: 01 May 2012 21:35 Title: tip: think sometimes very intense about it after that yes you durchfuehrst the tests no longer with sucrose, but with the products of the acid hydrolysis of sucrose. and if you nin is even a moment about it meditate on what products sucrose acid hydrolysis, then it should be obvious what happens you come on? greeting ingo _________________ saves a month in the laboratory a smooth but ne quarter of an hour at the library! Bubu Joined: 22/01/2012 Beitrge: 13 Posted: 01 May 2012 22:04 Title: So by the hydrolysis is indeed split into two parts as glucose and in the open-chain form of glucose has an aldehyde group, but I'm still confused why is the Seliwanow sample then positive? If that has an aldehyde group, itis which would have to be negative but, or I confuse something here? magician4 Moderator Joined: 05/10/2009 Beitrge: 8281 Location: Hamburg Posted: 01 May 2012 22:25 Title: Quote: So by the hydrolysis is yes no in two parts as glucose split (..), just not in which both sugar sucrose is digested? http://de.wikipedia.org/wiki/Saccharose greeting ingo _________________ saves a month in the laboratory a smooth but ne quarter of an hour at the library! Bubu Joined: 22/01/2012 Beitrge: 13 Posted: 01 May 2012 23:59 Title: ups, fructose and glucose in? but I kapiers still not really: itis P Bubu Joined: 22/01/2012 Beitrge: 13 Posted: 02 May 2012 12:07 Title: Oh, the unit that one probably the Fehling test nachweit that glucose in an aldehyde is present and the Seliwanow sample that is not present in fructose? magician4 Moderator Joined: 05/10/2009 Beitrge: 8281 Location: Hamburg Posted: 02 May 2012 00:58 Title: Quote: Oh the safety that one probably the Fehling test nachweit that glucose in an aldehyde is present and the Seliwanow sample that is not present in fructose? just eats! CN8 ingo _________________ saves a month in the laboratory a smooth but ne quarter of an hour in the library! Bubu Joined: 22/01/2012 Beitrge: 13 Posted: 02 May 2012 14:20 Title: itis okay thank you
Answers Forum overview -> Organic Chemistry Related Topics - The Latest Topics Replies Author Views Last Post sucrose 1 guest 212 11 June 2013 21:52 Daniel35 sucrose sugar 600 11 31 January 2013 09:59 Daniel35 why forms NaCl in aqueous solutions ions and sucrose 2 lilyfee 1210 28 December 2011 09:18 lilyfee fructose iodine number 12 2006 22 February itis 2011 22:49 magician4 sucrose reaction itis 3 Mutated! 2846 20 June 2008 11:52 Litterman Related Topics - the biggest Topics Replies Author Views Last Post fructose iodine number 12 2006 22 February 2011 22:49 magician4 sucrose sugar 600 11 31 January 2013 09:59 Daniel35 anomers of sucrose. 4 hard.rock. 1364 28 December 2005 11:50 Rumex sucrose reaction 3 Mutated! 2846 20 June 2008 11:52 Litterman reaction mechanism of sucrose with resorcinol 2 Ano 1407 28 February 2005 17:16 Ano (login error) Related Topics - The Most Popular Topics Replies Author Views Last Post sucrose reaction 3 Mutated! 2846 20 June 2008 11:52 Litterman Whlk reaction with glucose, fructose, lactose, sucrose 1 Mutated! 2707 20 June 2008 18:16 Mutated! Fructose 12 iodine value 2006 22 February 2011 22:49 magician4 reaction itis mechanism of sucrose with resorcinol 2 Ano 1407 28 Feb 2005 17:16 Ano (login error) anomers of sucrose. 4 hard.rock. itis 1364 28 December 2005 11:50 Rumex


No comments:

Post a Comment