1. Potassium persulphate is used in photography to remove the last traces of unwanted chemicals from photographic papers and plates. A 0.8162 g sample was found to contain 0.2361 g of potassium, 0.1936 g of sulphur and the rest was oxygen. What is the empirical formula of this compound? Prove with calculations.

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

alchemy hadn't scientific methods of study, appeal to mysticism and fantasy, the knowledge of chemistry and physics were modest at that time.

alchemy was - but as new rules were discovered it either changed into chemistry or it became "unscientific".