CHEMISTRY OXIDATION NUMBERS
please help me solve only 3 of those oxidation numbers

NO2
Cr2O72-
KCl
NH3
CaH2
SO42-
Na2O2
SiO2
CaCl2

An empty fuel tank can still contain and therefore can be even more dangerous than one full of liquid fuel.

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.

Which substance—wood or silver—is the better thermal conductor? a thermal conductor is a material that requires very little heat energy to change its temperature. explain your answer.