1. why pupil of the eye appears black in colour ?
2. How to test the evolution of. carbon dioxide gas in a chemical reaction.
3. Write a use of bifocal lens.?
Answers
Answer:
1.The pupil is a hole located in the centre of the iris of the eye that allows light to strike the retina. It appears black because light rays entering the pupil are either absorbed by the tissues inside the eye directly, or absorbed after diffuse reflections within the eye that mostly miss exiting the narrow pupil.
2.The most effective way to test for CO2 is to bubble the gas through "limewater", a diluted solution of calcium hydroxide (slaked lime). When you bubble carbon dioxide through the solution, it forms a solid precipitate of calcium carbonate – chalk or limestone.
3.Bifocal lenses are used in the spectacles of people suffering from presbyopia, myopia, hyperopia or/and astigmatism. These have two distinct powers and hence serves two functions. One is distant vision and the other is closeup vision.
PLEASE MARK AS BRAINLIEST.......
Answer:
Explanation:1. No light is reflected from the Pupil.
3.Bifocal lens is used by presbiopic person. Because neither they can see nearby objects nor farther objects.