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.

sodium (na), for example, has one electron in its valence shell. this is an unstable state because that valence shell needs eight electrons to be full. in order to fill its valence shell, find a way to add seven electrons to its valence shell

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.