. A 7.000- g sample of a pesticide (DDT, C14H9CI5 , 354.5 g/mol) was decomposed with metallic Na in alcohol, and the liberated chloride ion was precipitated as AgCI (143.32 g/mol). Express the results of this analysis in terms of percent DDT (m/m) based on the recovery of 0.2513 g AgCl.

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)

Iwould appreciate if someone could me.

The comparison of the number of atoms in a copper coin the size of a penny with the number of people on earth is made to illustrate which of the following? a. that atoms are indivisible b. that atoms are very small c. that atoms are very large d. that in a copper penny, there is one atom for every person on earth