High School Earth, Space, and Geophysical Curriculum Essentials May 2009 10. Boulder Valley School District High School Earth, Space, and Geophysical. Science Curriculum Essentials Document. If learning is to endure in a flexible, adaptable way for future use, then teachers must design units.
A curmudgeon with years of practice. Coal ash is the residue from burning coal and contains all of the nonvolatile components of he coal (carbon compounds, sulfur and some metals). The ash is made up of silicates, metals (including toxic metals like mercury and uranium) and some unburnt carbon.
In either case the tar is a by-product of the operation. Coal tar, a thick, black, oily liquid of sp. gr. I.1 to 1.2 5, is obtained with ammoniacal liquor when the volatile products of the carbonization of coal are cooled.On settling, the distillate separates into two layers, and the aqueous ammoniacal liquor is drawn off from above the tar.hese variations from normal tar are due to the fact that many of the products of distillation are removed from the reaction chamber before the coal has reached its final high temperature. Vertical retort tar, therefore, has some of thv characteristics of low-temperature tar (see TARS, LOW-TEMPERATURE).