Explain how a scientific theory differs from a guess or an opinion?

Consider the nuclear equation below. 239/94 pu—-> x+ 4/2 he. what is x?

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?

You just calculated that the heat of fusion for chloromethane is 6400 j/mol. the heat of fusion for hydrogen is 120 j/mol.? which of the following account for this difference? more than one correcta. chloromethane can absorb more energy at the same temperature. b. hydrogen has stronger intermolecular forces than chloromethane. c. hydrogen molecules can pack more closely than chloromethane molecules. d. chloromethane experiences dipole-dipole interactions. e. chloromethane has a higher molar mass than hydrogen.