Demonstration showing the immiscibility of water and hexane, an alkane hydrocarbon with six carbon atoms. Initially the beaker contains water, and then hexane is poured in from a bottle. Water is a polar solvent, which has a separation of charge due to its electronegative oxygen atom. By contrast, hexane is non-polar, having a symmetrical linear molecule with no charge separation. Hexane and water are completely immiscible, and the hexane is seen to form a separate layer above the water, due to its lower density.