Question

Why does methyl orange stain worsted wool so well? Explain using intermolecular forces.

Answer 1

Looking at the chemical structures of Worsted Wool, there is a lot hydrogen bonding that occurs through out the structure, in addition to the dispersion forces. The methyl orange can easily hydrogen bond with the nitrogen atoms on the wool, and hydrogen bonding is considered to cause very strong inter molecular force which is why the dye will hold onto the fabric really well. That is what leads to the dye holding on to that fabric really well, and forming a bright color. There are additional forces that also contribute to the fact that the dye holds onto the fabric so strongly, and that’s because of the dipole-dipole moments within the Wool molecule. This is why, even despite the bleaching, the orange color stayed on this part of the color pretty strongly. (Wool is a protein—a naturally occurring polymer made up of amino acid repeating units. Many of the amino acid units have acidic or basic side chains that are ionized (charged). The presence of many charged groups in the structure of wool provides excellent binding sites for dye moleculesi(methylorange), most of which are also charged.