00273nam a2200109Ia 450000500170000000800410001708200120005810000210007024500240009126000400011530000080015520260224040821.0260224s9999||||xx |||||||||||||| ||und||  a540 CHO  aChoudhary, C.K.  0aBasics of chemistry  aNew York: Rosen Publications c2009  a289