Sb2O3 (Antimony trioxide)
Sb2O3, also known as antimony trioxide, is a white solid compound. It is composed of two antimony (Sb) atoms bonded to three oxygen (O) atoms. The compound has a molecular formula of Sb2O3 and a molar mass of 291.52 g/mol. It is primarily used as a flame retardant, as well as in the manufacturing of glass, ceramics, and paints.

Color of Sb2O3
The white color of Sb2O3 can be attributed to its electronic structure and the way it interacts with light. When light strikes a substance, it can be either absorbed, transmitted, or reflected. The color we perceive is the result of the wavelengths of light that are reflected back to our eyes.

Electronic structure of Sb2O3
Sb2O3 has a crystal structure composed of antimony ions (Sb3+) and oxide ions (O2-). The antimony ions have a +3 oxidation state, while the oxide ions have a -2 oxidation state. The compound forms a network of Sb3+ and O2- ions held together by ionic bonds.

Light absorption and reflection
The white color of Sb2O3 is due to its ability to reflect most of the visible light that falls on its surface. In other words, it does not absorb light in the visible spectrum and instead reflects a significant portion of it back to our eyes. As a result, we perceive it as white.

Sb2S3 (Antimony trisulfide)
Sb2S3, also known as antimony trisulfide, is an orange-yellow solid compound. It is composed of two antimony (Sb) atoms bonded to three sulfur (S) atoms. The compound has a molecular formula of Sb2S3 and a molar mass of 339.68 g/mol. It is primarily used as a pigment in the production of fireworks and as a catalyst in certain chemical reactions.

Color of Sb2S3
The orange-yellow color of Sb2S3 can be attributed to its electronic structure and the way it interacts with light. As with Sb2O3, the color we perceive is the result of the wavelengths of light that are reflected back to our eyes.

Electronic structure of Sb2S3
Sb2S3 has a crystal structure composed of antimony ions (Sb3+) and sulfide ions (S2-). The antimony ions have a +3 oxidation state, while the sulfide ions have a -2 oxidation state. The compound forms a network of Sb3+ and S2- ions held together by ionic bonds.

Light absorption and reflection
The orange-yellow color of Sb2S3 is due to its ability to selectively absorb and reflect certain wavelengths of light. It absorbs blue and violet light while reflecting longer wavelengths in the orange and yellow range. This absorption and reflection pattern gives rise to the characteristic color of Sb2S3.

Overall, the difference in color between Sb2O3 (white) and Sb2S3 (orange-yellow) can be explained by their unique electronic structures and the way they interact with light.