The grams of caH2 that are needed to generate 143 L of H2 is calculated as follows by use of ideal gas equation Pv=nRT where n is number of moles, calculate the moles of H2 produced by making n the subject of the formula n= PV/RT p= 827 torr R(gas constant)= 62.36 L.torr/mol.K T= 273 +22=295 k V=143 L n =(827 torr x143 L)/ 62.36 L.torr/mol.k x295 k) =6.43 moles
write the reacting equation that is caH2 +2H2O= Ca(OH)2 + 2H2
by use of mole ratio between CaH2 to H2 which is 1 :2 the moles of CaH2 = 6.43 x1/2=3.215 moles
mass of CaH2 is therefore= moles of CaH2 x molar mass of CaH2
