Scientists pam and alejandro were discussing a liquid found in the science lab that was missing it's label. in classifying the unknown liquid, they first needed to determine if the liquid is a mixture or pure substance. how is a pure substance different from a mixture mixtures cannot be separated by physical means. a pure substance is heterogeneous. pure substances cannot be separated by physical means. a mixture is made of one substance.

The correct answer is option C. Pure substances cannot be separated by physical means.

Matter is composed of mixtures and pure substances. Pure substances can be further simplified into elements and compounds. Mixtures are physically combined of different components. Pure substances cannot be separated by physical means whereas mixtures can be separated by physical means such as decantation, sedimentation, filtration, distillation and more.