Is it safe to remove slides from the microscope when the 100X is in place and the stage is not moved?

It is generally not safe to remove slides from the microscope when using the 100X objective lens, even if the stage is not moved. The high magnification can bring the slide very close to the lens, increasing the risk of damaging the slide, the lens, or both. It's best to lower the objective lens or use a lower magnification before removing the slide to avoid any potential contact or damage.