Which criteria are responsible for deciding whether a heterogeneous mixture is a colloid or a suspension? 
whether its composition is uniform and transparent whether the particles remain suspended for an extended period of time
whether it can be separated into simpler substances through physical separation techniques
whether the ratio of components is fixed

Both josef loschmidt and amedeo avogadro contributed to our understanding of basic molecular numbers, sizes, and reaction ratios. neither scientist discovered “avogadro’s number” in the form we use it today (6.02 x 10 23). still, there’s a controversy over the name. research the contributions from these two scientists and read about how avogadro’s number got its name. briefly state what you think this number should be called, providing key details of each scientist’s contributions to this concept and a solid rationale for your case in naming the number.

An observation that requires measurement is called quantitative observable or qualitative

Jose and eric were given four samples in lab. the results of their analysis are shown in the table. based on the data they collected, which sample is most likely a metal?