251. Please e-mail, and the material balance of the following reactions:
KMnO4 + Na2SO3 + KOH K2MnO4 + Na2SO4 + H2O
H2SO4 + H2S S0 + H2O
P + KOH + H2O KH2PO4 + PH3
KMnO4 + Na2SO3 + H2O MnO2 + Na2SO4 + KOH.
Tasks performed in Microsoft Word, typed in the formula editor MathType (if formulas are unreadable signs, then you need to install the editor); files are archived WinRAR.