Which phenomenon provides evidence that light
has a wave nature?
(1) emission of light from an energy-level
transition in a hydrogen atom
(2) diffraction of light passing through a narrow
opening
(3) absorption of light by a black sheet of paper
(4) reflection of light from a mirror

(2) diffraction of light passing through a narrow  opening

Explanation:

As we know that when light passes through a small opening then the wavefront that passes  through small opening will behave like a combination of large number of point sources.

Each point source will emit a wave and due to superposition of all such waves we can observe a pattern of maximum and minimum on the screen.

this is given by the equation

so here we can say that the correct answer will be

(2) diffraction of light passing through a narrow  opening

vapour or gas assuming atmospheriv pressure

energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical means. do not understand what you are asking but hope this