How is the periodic table generally arranged?

How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.

Amixture that has two or more substances that are spread out evenly is called a. compound b. heterogeneous c. substance d. homogeneous

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)