下列属于纯净物的是请选择DCBA(K,P8z,r0E/?'?'{:^(J8m8~5F+C4O._5N;w2?
A.稀硫酸'?'{:^(J8m8~5F+C4O._5N;w2?
B.氯化钾'?'{:^(J8m8~5F+C4O._5N;w2?
C.石油'?'{:^(J8m8~5F+C4O._5N;w2?
D.空气'?'{:^(J8m8~5F+C4O._5N;w2?