True or false, the nucleus is the core of an atom

What is the formula for the compound dinitrogen pentoxide? a. n4o5 b. n5o4 c. n4o6 d. n5o2 e. n2o5

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

Which is an example of the practical pursuit of alchemy? a. forming perfect substances. b. transforming base metals. c. developing metalworking techniques. d. linking spiritual characteristics with material substances.