A simple and rapid method to obtain a linear density gradient

Abstract

A method is outlined and apparatus described to prepare rapidly and conveniently a reproduceable linear density gradient of any low-to-high value. The apparatus consists of two prismatic connected vessels of triangular shape one of which is inverted and tilted to a pre-calculated degree to account for the density difference of the liquids in the vessels. The liquids emerge, by gravitational levelling, from a common efflux tube connecting the vessels. 30 ml of density gradient can be withdrawn in 5 min. The linearity of the etflux is theoretically derived and shown experimentally using a number of organic liquids.