The chemical equations provided are as follows:

H2 + P = 2HCl (hydrogen gas reacts with phosphorus to form hydrochloric acid)C + O2 = CO2 (carbon reacts with oxygen to form carbon dioxide)MgI2 + Cl2 = MgCl2 + I2 (magnesium iodide reacts with chlorine gas to form magnesium chloride and iodine)