How does the density of a solution affect the light's travel through it when using a refractometer?

The correct understanding of how density affects light's travel through a solution with a refractometer centers around the principles of refraction and the interactions of light with different mediums. As the density of a solution increases, its refractive index also typically increases. When light passes from one medium to another—such as from air into a denser liquid—it slows down and changes direction. This phenomenon is governed by Snell's Law, which illustrates how the angle of incidence and the indices of refraction of the two media relate to one another.

In denser solutions, light travels more slowly due to the increased mass and the intermolecular interactions within the denser medium. Consequently, the path of the light is bent more significantly, leading to greater refraction. This property is critical in the calibration and use of a refractometer, which relies on measuring this refractive index to ascertain the concentration of solutes in a solution.

The other options fail to capture this fundamental behavior of light. Any implication that increased density results in a faster travel time for light overlooks the basic principles of optics, and stating that density does not affect light travel entirely misses the critical impact of refractive index on light behavior. Additionally, suggesting that more light passes through without refraction contradict