which of the following is an empirical formula A.C2H5 B.C2H8 C.CH4 D.C4H10

Answer 1

The empirical formula is the one with the lowest whole number subscripts. C2H8 and C4H10 can be reduced to CH4 and C2H5, which can't be reduced further to whole numbers, so CH4 and C2H5 are the empirical formulas.