Use the bond energies provided to estimate δh°rxn for the reaction below. hint: draw the lewis structures for reactants and products to determine the number of bonds pcl3(g) + cl2(g) → pcl5(l) δh°rxn = ?

Which statement correctly describes metallic bonds? a. they form when certain atoms lose electrons and other atoms gain electrons. b. they involve an attraction between anions and cations. they always involvpoth a metal and a nonmetal. d. they can only form between atoms of the same element. e. they form because electrons can move freely between atoms.

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?