CNG is made by compressing natural gas (which is mainly composed of methane, CH4), to less than 1 percent of the volume it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of 20â25 MPa (2,900â3,600 psi), usually in cylindrical or spherical shapes.
Definition of chromophore - an atom or group whose presence is responsible for the colour of a compound. Definition of chromophore - an atom or group whose presence is responsible for the colour of a compound.
An auxochrome (Greek Î±á½Î¾Î¬Î½ÎµÎ¹Î½ auxÃ¡nein: to increase and ÏÏá¿¶Î¼Î± chrÅma: colour) is a group of atoms attached to a chromophore which modifies the ability of that chromophore to absorb light. They themselves fail to produce the colour; but when present along with the chromophores in an organic compound intensifies the colour of the chromogen.