On a clear day, you can see Puerto Rico from the Dominican Republic if you are at a high elevation, such as on a mountain or hill. For example, you can see Puerto Rico from Pico Duarte, the highest peak in the Dominican Republic. However, if you are at sea level, it is unlikely that you will be able to see Puerto Rico, even on a clear day.
Atmospheric conditions can also affect the visibility of Puerto Rico from the Dominican Republic. If there is a lot of haze or dust in the air, it will be more difficult to see Puerto Rico. Similarly, if there are clouds in the sky, it may block your view of Puerto Rico.
Finally, the time of day can also affect the visibility of Puerto Rico from the Dominican Republic. The best time to see Puerto Rico is early in the morning or late in the afternoon when the sun is low in the sky. This is because the sun's rays are less likely to be scattered by the atmosphere, making it easier to see distant objects.