Question

Let’s say that you have a solvatochromic compound that appears red in a solvent. You dissolve the compound in another solvent and it changes to an orange color. Would this be considered a hypsochromic or bathchromic shift? Would the solvent be more polar or less than the first solvent? Explain.

Answer 1

Answer:

Hypsochromic shift.

The second solvent is more polar.

Explanation:

Compound A + Solvent 1 = red

Compound A + Solvent 2 = orange

Since orange has a smaller wavelength than red, the electronic transition observed when the compound A is dissolved in solvent 2 has a higher energy.

A band transition to a lower wavelength and higher energy is called a hypsochromic shift.

The change in the color due to the solvent is called solvatochromism. Usually, when the hypsochromic shift is observed (negative solvatochromism) it means that the solvent is more polar.