Transcript Chapter 46: Dyes and Dyeing Diazotization of Sulfanilic Acid Preparation of Methyl Orange

Chapter 46
Dyes and Dyeing
Diazotization of Sulfanilic Acid
&
Preparation of Methyl Orange
Purpose
• In this experiment a separately prepared diazonium
salt is coupled with N,N-dimethylaniline in a weakly
acidic solution to give Methyl Orange.
• The product is isolated by filtration and dried between
two pieces of filter paper.
Comments
• Follow pp. 635-636, 639-640 (microscale).
• Follow the lab handout for all experimental
procedures. Wearing rubber gloves is
necessary during this lab. You will work with
toxic and corrosive compounds.
• Calculate yield. Moderate to good yields
should be achieved.
(Moles Product / Moles Starting Material) x
100 = % Yield
Safety
• Sulfanilic acid is irritating to eyes, respiratory
system and skin. May cause sensitization by
skin contact. Do not swallow, do not inhale
and avoid contact with eyes and skin. Wear
gloves and handle with caution.
• N,N-Dimethylaniline is toxic by inhalation, in
contact with skin and if swallowed. Limited
evidence of carcinogenic effects. Do not
swallow, do not inhale and avoid contact with
eyes and skin. Wear protective gloves and
goggles.
• HCl is corrosive, wear gloves and use caution.