The mass of tin produced from 0.211 moles of hydrogen is calculated as follows
by writing the reaction equation
that is
SnO2 + 2H2 ----> Sn + 2H2O
by use of mole ratio the between H2 to Sn which is 2:1
the moles of Sn is therefore = 0.211/2=0.1055 moles
mass = moles x molar mass of Sn
that is 0.1050 x 118.71 grams
