Bonjours j’ai besoin d’aide! C’est pour demain! 1. D'après les résultats obtenus après révélation sous U. V., indiquer si l'extrait naturel d'amande amère (AA)
est constitué uniquement de benzaldéhyde (B).

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656 nm(red) and 486 nm (blue). light from a hydrogen lamp illuminates a diffraction grating with 520lines/mm , and the light is observed on a screen 1.5m behind the grating. part a what is the distance between the first-order red and blue fringes? express your answer to two significant figures and include the appropriate units.

Ablock of mass 1.5 kg slides down an inclined plane that has an angle of 15. if the inclined plane has no friction and the block starts at a height of 3 m, how much kinetic energy does the block have when it reaches the bottom? acceleration due to gravity is g = 9.8 m/s2. a. 6.8 j b. 50.9 j c. 0 j d. 44.1 j

Which of the following are considered noble gases? a. bromine b. neon c. argon d. chlorine