Can someone please help?? Which type of test helps forensic scientists to narrow down the possibilities of what drug a substance may be?

How does the motion of particles in a gas change as the gas cools

Which statement best describes what happens when molecular compounds melt

With the largest atoms and the smallest number of valence electrons and with the smallest atoms and the greatest number of valence electrons are the most reactive. a. nonmetals; metals b. nonmetals; transition elements c. transition elements; metals d. metals; nonmetals