A0.45-g sample of aspirin is decomposed into its constituent elements and found to contain 0.27 g c, 0.020 g h, and 0.16 g o. part a calculate the mass percent composition of c, h, and o in aspirin. express your answers to two significant figures. en

Mass % of C = 0.27/0.45*100 = 60% H = 0.02/0.45*100 = 4.4% O = 0.16/0.45*100 = 35.6% Total = 60%+4.4%+ 35.6% = 100% - OK To 2 significant figures C=60.%, (Note the . after the 60) , H = 4.0% , O =36% Note : in order to write the %O as 2 sig figs we have had to write the %H as 4.0 % .

They are all full and don't need any more electrons in there outer shell.

Coal i believe hope this