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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: lovelyangle on September 25, 2007, 04:55:08 PM

Title: Questions about cr(acac)3 exp.
Post by: lovelyangle on September 25, 2007, 04:55:08 PM
hi

we synthesis cr(acac)3 and i want your help to answer some questions about it >>

1 - why is NaOH not used (instead of urea) to make the solution basic ?

2- how does urea make the solution basic ?

3- why was a steam bath used to heat the reaction flask instead of a direct flame ?

please help me

>>  
Title: Re: Questions about cr(acac)3 exp.
Post by: AWK on September 26, 2007, 01:33:49 AM
1. NaOH decomposes complex
2. http://www.colby.edu/chemistry/Grants/CH141L4Crfall2002.pdf
3. Safety
Title: Re: Questions about cr(acac)3 exp.
Post by: lovelyangle on September 26, 2007, 01:48:36 PM
thx

how i can improve the percentage yeild ??

>>
Title: Re: Questions about cr(acac)3 exp.
Post by: AWK on September 27, 2007, 12:53:21 AM
Usuallay an excess of acac is used
Title: Re: Questions about cr(acac)3 exp.
Post by: mahesh on October 19, 2007, 09:50:15 AM
acac is acetylacetonate. The complex would hydrolyse if you use NaOH, hence urea is used. Read why -NH2 group has basicity.
acac complexes usually give high yields. I have prepared acac complexes of many metals, and had no issues of yield. You always use slight excess of the ligands while making organometallic complexes.
Title: Re: Questions about cr(acac)3 exp.
Post by: hala on October 24, 2007, 01:34:01 PM
hi

we synthesis cr(acac)3 and i want your help to answer some questions about it >>

1 - why is NaOH not used (instead of urea) to make the solution basic ?

2- how does urea make the solution basic ?

3- why was a steam bath used to heat the reaction flask instead of a direct flame ?

please help me

>>